NilsML/retriever_dataset · Datasets at Hugging Face

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Animals use saturated fatty acids to store what?	water	blood	hydrogen	energy	Animals use saturated fatty acids to store energy. Plants use unsaturated fatty acids to store energy.
The atmospheric concentration of carbon dioxide on earth has been regulated by the concentration of what form of life?	seaweed	fruit	fungus	plant	Homeostasis is a term that is also used when talking about the environment. For example, the atmospheric concentration of carbon dioxide on Earth has been regulated by the concentration of plant life on Earth, because plants remove more carbon dioxide from the atmosphere during the daylight hours than they emit to the atmosphere at night.
What organisms have a life cycle that includes alternation of generations?	insects	fungi	animals	plants	All plants have a characteristic life cycle that includes alternation of generations.
What are nekton animals able to do in water?	reproduce	breath	lay eggs	move on their own, swim	Nekton are aquatic animals that can move on their own by “swimming” through the water. They may live in the photic or aphotic zone. They feed on plankton or other nekton. Examples of nekton include fish and shrimp.
What is a property of a system whose magnitude depends on only the present state of the system, not its previous history?	intensive function	extensive function	laplacian	state function	conserved. The state of a system is a complete description of a system at a given time, including its temperature and pressure, the amount of matter it contains, its chemical composition, and the physical state of the matter. A state function is a property of a system whose magnitude depends on only the present state of the system, not its previous history. Temperature, pressure, volume, and potential energy are all state functions. The temperature of an oven, for example, is independent of however many steps it may have taken for it to reach that temperature. Similarly, the pressure in a tire is independent of how often air is pumped into the tire for it to reach that pressure, as is the final volume of air in the tire. Heat and work, on the other hand, are not state functions because they are path dependent. For example, a car sitting on the top level of a parking garage has the same potential energy whether it was lifted by a crane, set there by a helicopter, driven up, or pushed up by a group of students (). The amount of work expended to get it there, however, can differ greatly depending on the path chosen. If the students decided to carry the car to the top of the ramp, they would perform a great deal more work than if they simply pushed the car up the ramp (unless, of course, they neglected to release the parking brake, in which case the work expended would increase substantially!). The potential energy of the car is the same, however, no matter which path they choose.
Prokaryotic cells lack what key structure and other membrane-bound organelles?	proton	cell wall	epidermis	nucleus	Prokaryotic cells lack a nucleus and other membrane-bound organelles.
All of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as what?	particles ' s metabolism	slowed metabolism	genetic metabolism	cell ' s metabolism	4.1 \| Energy and Metabolism By the end of this section, you will be able to: • Explain what metabolic pathways are • State the first and second laws of thermodynamics • Explain the difference between kinetic and potential energy • Describe endergonic and exergonic reactions • Discuss how enzymes function as molecular catalysts Scientists use the term bioenergetics to describe the concept of energy flow (Figure 4.2) through living systems, such as cells. Cellular processes such as the building and breaking down of complex molecules occur through stepwise chemical reactions. Some of these chemical reactions are spontaneous and release energy, whereas others require energy to proceed. Just as living things must continually consume food to replenish their energy supplies, cells must continually produce more energy to replenish that used by the many energy-requiring chemical reactions that constantly take place. Together, all of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as the cell’s metabolism.
In genetic drift, chance fluctuations in allele frequencies over generations tend to reduce what?	genetic entanglement	biochemical variation	responsible variation	genetic variation	null
What gives the order of electron filling in an atom?	periodic table	orbit order	Bohr's law	aufbau principle	The Aufbau principle gives the order of electron filling in an atom.
What occurs whenever an unbalanced force acts on an object?	vibration	compression	inertia	acceleration	Whenever an object speeds up, slows down, or changes direction, it accelerates. Acceleration occurs whenever an unbalanced force acts on an object. Two factors affect the acceleration of an object: the net force acting on the object and the object’s mass. Newton’s second law of motion describes how force and mass affect acceleration. The law states that the acceleration of an object equals the net force acting on the object divided by the object’s mass. This can be represented by the equation:.
What are large collections of millions or billions of stars called?	orbits	fragments	universe	galaxies	Galaxies are collections of millions to many billions of stars.
What is the developmental process of gastropods called?	occlusion	regeneration	modulation	torsion	null
Name one unit used to measure pressure.	decibel	watt	meter	torr	Pressures are given in a multitude of units. We've already discussed Pascals, and we know that another unit for pressure is the atmosphere (1 atm = 101.3 x 10 5 Pa). The third commonly used pressure unit is the torr (symbol: Torr). 760 torr is 1 atm, but 1 torr is also the increase in pressure necessary to cause liquid mercury to rise by 1 mm. For that reason, torr is also commonly referred to as "millimeters mercury. " Another pressure unit commonly used in our everyday world is psi, or pounds per square inch, though neither psi nor torr are SI units.
Eggs and sperm are not somatic cells but instead what kind of cells?	Sickness	toxins	pollen	germ	So far in this chapter, you have read numerous times of the importance and prevalence of cell division. While there are a few cells in the body that do not undergo cell division (such as gametes, red blood cells, most neurons, and some muscle cells), most somatic cells divide regularly. A somatic cell is a general term for a body cell, and all human cells, except for the cells that produce eggs and sperm (which are referred to as germ cells), are somatic cells. Somatic cells contain two copies of each of their chromosomes (one copy received from each parent). A homologous pair of chromosomes is the two copies of a single chromosome found in each somatic cell. The human is a diploid organism, having 23 homologous pairs of chromosomes in each of the somatic cells. The condition of having pairs of chromosomes is known as diploidy. Cells in the body replace themselves over the lifetime of a person. For example, the cells lining the gastrointestinal tract must be frequently replaced when constantly “worn off” by the movement of food through the gut. But what triggers a cell to divide, and how does it prepare for and complete cell division? The cell cycle is the sequence of events in the life of the cell from the moment it is created at the end of a previous cycle of cell division until it then divides itself, generating two new cells.
Regular checkups with what type of specialist can detect skin cancers early?	internist	endocrinologist	nephrologist	dermatologist	Regular checkups with a dermatologist can detect skin cancers early. Why is early detection important?.
Receptors for what sense are located within sensory hairs on the feet of insects, as well as in mouthparts?	smell	touch	sight	taste	null
Where does the stored energy in fossil fuels originally come from, before it changed forms several times?	decomposers	the Moon	Earth's core	the sun	Fossil fuels contain stored chemical energy that came originally from the sun. Ancient plants changed energy in sunlight to stored chemical energy in food, which was eaten by other organisms. After the plants and other organisms died, their remains gradually changed to fossil fuels as they were pressed beneath layers of sediments. Petroleum and natural gas formed from marine organisms and are often found together. Coal formed from giant tree ferns and other swamp plants.
A prokaryote is a simple, mostly single-celled organism that lacks what key organelle?	ribosome	chloroplast	golgi apparatus	nucleus	are found; 3) DNA, the genetic material of the cell; and 4) ribosomes, which synthesize proteins. However, prokaryotes differ from eukaryotic cells in several ways. A prokaryote is a simple, mostly single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle. We will shortly come to see that this is significantly different in eukaryotes. Prokaryotic DNA is found in a central part of the cell: the nucleoid (Figure 4.5).
Increasing the surface area of solid reactants increases what rate?	breathing	fusion	metabolism	reaction	When a solid substance is involved in a chemical reaction, only the matter at the surface of the solid is exposed to other reactants. If a solid has more surface area, more of it is exposed and able to react. Therefore, increasing the surface area of solid reactants increases the reaction rate. Look at the hammer and nails pictured in the Figure below . Both are made of iron and will rust when the iron combines with oxygen in the air. However, the nails have a greater surface area, so they will rust faster.
Epithelial cells are found in what body organ?	liver	lungs	brain	skin	DNA Replication In order for an organism to grow, develop, and maintain its health, cells must reproduce themselves by dividing to produce two new daughter cells, each with the full complement of DNA as found in the original cell. Billions of new cells are produced in an adult human every day. Only very few cell types in the body do not divide, including nerve cells, skeletal muscle fibers, and cardiac muscle cells. The division time of different cell types varies. Epithelial cells of the skin and gastrointestinal lining, for instance, divide very frequently to replace those that are constantly being rubbed off of the surface by friction. A DNA molecule is made of two strands that “complement” each other in the sense that the molecules that compose the strands fit together and bind to each other, creating a double-stranded molecule that looks much like a long, twisted ladder. Each side rail of the DNA ladder is composed of alternating sugar and phosphate groups (Figure 3.23). The two sides of the.
What's the name for an organic compound in which halogen atoms are substituted for hydrogen in a hydrocarbon?	alcohol	sodium halide	glucose	alkyl halide	An alkyl halide is an organic compound in which one or more halogen atoms are substituted for one or more hydrogen atoms in a hydrocarbon. The general formulas for organic molecules with functional groups use the letter R to stand for the rest of the molecule outside of the functional group. Because there are four possible halogen atoms (fluorine, chlorine, bromine, or iodine) that can act as the functional group, we use the general formula R−X to represent an alkyl halide. The rules for naming simple alkyl halides are listed below.
The trachea and bronchi are made of incomplete rings of this?	ligaments	membrane	collagen	cartilage	Figure 39.8 The trachea and bronchi are made of incomplete rings of cartilage. (credit: modification of work by Gray's Anatomy).
What do we call cyclones that form in tropical latitudes?	eruptions	twister	disturbances	hurricanes	Hurricanes are cyclones that form in tropical latitudes. They are called tropical cyclones.
Which amino acid do organisms incorporate into their proteins?	glutamate	histone	peptide	arginine	null
What fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms?	trilobites	coal	sediment	fossil	Oil, or petroleum, is one of several fossil fuels . Fossil fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms. In addition to oil, they include coal and natural gas. Fossil fuels provide most of the energy used in the world today. They are burned in power plants to produce electrical energy, and they also fuel cars, heat homes, and supply energy for many other purposes. You can see some ways they are used in the Figure below . For a more detailed introduction to fossil fuels, go to this URL: http://www. ecokids. ca/pub/eco_info/topics/energy/ecostats/index. cfm.
What is the cartilaginous structure that extends from the pharynx to the primary bronchi?	sternohyoid	larynx	cricoid	trachea	Chapter 39 1 Figure 39.7 B 3 Figure 39.20 The blood pH will drop and hemoglobin affinity for oxygen will decrease. 4 A 6 B 8 D 10 B 12 D 14 C 16 The main bronchus is the conduit in the lung that funnels air to the airways where gas exchange occurs. The main bronchus attaches the lungs to the very end of the trachea where it bifurcates. The trachea is the cartilaginous structure that extends from the pharynx to the primary bronchi. It serves to funnel air to the lungs. The alveoli are the sites of gas exchange; they are located at the terminal regions of the lung and are attached to the respiratory bronchioles. The acinus is the structure in the lung where gas exchange occurs. 18 FEV1/FVC measures the forced expiratory volume in one second in relation to the total forced vital capacity (the total amount of air that is exhaled from the lung from a maximal inhalation). This ratio changes with alterations in lung function that arise from diseases such as fibrosis, asthma, and COPD. 20 Oxygen moves from the lung to the bloodstream to the tissues according to the pressure gradient. This is measured as the partial pressure of oxygen. If the amount of oxygen drops in the inspired air, there would be reduced partial pressure. This would decrease the driving force that moves the oxygen into the blood and into the tissues. P O is also reduced at high elevations: P O at high elevations is lower than 2.
Excess dietary fat is stored as triglycerides in the body. what type of tissue is used to store the triglycerides?	metabolic	connective	muscle	adipose	inside these cells, glucose is immediately converted into glucose-6-phosphate. By doing this, a concentration gradient is established where glucose levels are higher in the blood than in the cells. This allows for glucose to continue moving from the blood to the cells where it is needed. Insulin also stimulates the storage of glucose as glycogen in the liver and muscle cells where it can be used for later energy needs of the body. Insulin also promotes the synthesis of protein in muscle. As you will see, muscle protein can be catabolized and used as fuel in times of starvation. If energy is exerted shortly after eating, the dietary fats and sugars that were just ingested will be processed and used immediately for energy. If not, the excess glucose is stored as glycogen in the liver and muscle cells, or as fat in adipose tissue; excess dietary fat is also stored as triglycerides in adipose tissues. Figure 24.21 summarizes the metabolic processes occurring in the body during the absorptive state.
What do you call winds that occur in belts that go all around the planet?	solar winds	rotational winds	gravitational winds	global winds	Global winds are winds that occur in belts that go all around the planet. You can see them in Figure below . Like local winds, global winds are caused by unequal heating of the atmosphere.
What property is a property that depends on the amount of matter in a sample?	non-exact	provided	relative	extensive	Some properties of matter depend on the size of the sample, while some do not. An extensive property is a property that depends on the amount of matter in a sample. The mass of an object is a measure of the amount of matter that an object contains. A small sample of a certain type of matter will have a small mass, while a larger sample will have a greater mass. Another extensive property is volume . The volume of an object is a measure of the space that is occupied by that object.
The legend explains features and symbols on?	earth	telescopes	compass	map	Look for the legend on the top left side of the map. The legend explains other features and symbols on the map.
Organic acids such as acetic acid all contain a functional group called what?	ester group	glycoprotein group	protein	carboxyl group	Organic acids such as acetic acid all contain a functional group called a carboxyl group .
Which is the only organ system in humans that differs greatly between males and females?	neural system	digestive system	immune system	reproductive system	Dogs have puppies. Cats have kittens. All organisms reproduce, obviously including humans. Like other mammals, humans have a body system that controls reproduction. It is called the reproductive system . It is the only human body system that is very different in males and females. The male and female reproductive systems have different organs and different functions.
Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the what membrane?	mucous	cutaneous	serous	tympanic	Figure 36.13 Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the tympanic membrane. The middle ear contains three bones called ossicles that transfer the sound wave to the oval window, the exterior boundary of the inner ear. The organ of Corti, which is the organ of sound transduction, lies inside the cochlea. (credit: modification of work by Lars Chittka, Axel Brockmann).
What is the most common cause of hearing loss?	quiet sounds	birth defect	infection	loud sounds	Many activities expose people to dangerously loud sounds that can cause hearing loss.
Some products contain iron filings that will react with air to release what type of energy?	spectral	physical	mechanical	thermal	Hikers, campers, and other outdoor folks take advantage of chemical reactions to keep their hands warm. Small containers of chemicals can undergo reaction to generate heat that can be used to avoid frostbite. Some products contain iron filings that will react with air to release thermal energy. These types of warmer cannot be reused. Other systems rely on heat being released when certain chemicals crystallize. If the warmer is placed in very hot water after use, the system can be regenerated.
Mutations in what type of regulatory gene can cause misplacement of structures in an animal?	myogenic	dichotic	diploid	homeotic	null
By what processes do rivers create floodplains?	deposition and sedimentation	depletion and erosion	thrust and deposition	erosion and deposition	Erosion and deposition by slow-flowing rivers creates broad floodplains and meanders.
What biological agents that infect living hosts contain dna, yet lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes?	bacteria	parasites	worms	viruses	Viruses contain DNA but not much else. They lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes. Therefore, viruses are not cells, but are they alive? All living things not only have cells; they are also capable of reproduction. Viruses cannot reproduce by themselves. Instead, they infect living hosts, and use the hosts’ cells to make copies of their own DNA. Viruses also do not have their own metabolism or maintain homeostasis. For these reasons, most scientists do not consider viruses to be living things.
An extensive property is a property that depends on the amount of what in a sample?	water	plasma	space	matter	An extensive property is a property that depends on the amount of matter in a sample.
A wheel with a rope wrapped around it, hanging over a building, is an example of what type of machine?	simple machine	pedal	propeller	pulley	This rusty iron wheel has a rope wrapped around it. The wheel and rope hang over a building. Together they make up a type of machine called a pulley.
Early types of what animals were the first vertebrates that moved onto land and have true lungs, although they had to return to the water to reproduce?	reptiles	mammals	birds	amphibians	The first vertebrates moved onto land about 365 million years ago. They were early amphibians. They were the first animals to have true lungs and limbs for life on land. However, they still had to return to the water to reproduce. That’s because their eggs lacked a waterproof covering and would dry out on land.
Many heterocyclic amines occur naturally in what?	animals	gases	nuclei	plants	nucleic acids, which in turn compose the genetic material of cells and direct protein synthesis. (For more information about nucleic acids, see Chapter 19 "Nucleic Acids". ) Many heterocyclic amines occur naturally in plants. Like other amines, these compounds are basic. Such a compound is an alkaloid, a name that means “like alkalis. ” Many alkaloids are physiologically active, including the familiar drugs caffeine, nicotine, and cocaine.
What do wind turbines change the kinetic energy of the wind into?	transportable energy	potential energy	available energy	electrical energy	Wind is moving air, so it has kinetic energy that can do work. Remember the wind turbines that opened this chapter? Wind turbines change the kinetic energy of the wind to electrical energy. Only certain areas of the world get enough steady wind to produce much electricity. Many people also think that wind turbines are noisy and unattractive in the landscape.
Population growth depends on birth rates and death rates, as well as what?	marriage	industrialization	communication	migration	Population growth rate depends on birth rates and death rates, as well as migration. First, we will consider the effects of birth and death rates. You can predict the growth rate by using this simple equation: growth rate = birth rate – death rate.
The exchange of heat stops once what property of equilibrium between the pan and the water is achieved?	motion	density	viscosity	thermal	of 150ºC . Assume that the pan is placed on an insulated pad and that a negligible amount of water boils off. What is the temperature when the water and pan reach thermal equilibrium a short time later? Strategy The pan is placed on an insulated pad so that little heat transfer occurs with the surroundings. Originally the pan and water are not in thermal equilibrium: the pan is at a higher temperature than the water. Heat transfer then restores thermal equilibrium once the water and pan are in contact. Because heat transfer between the pan and water takes place rapidly, the mass of evaporated water is negligible and the magnitude of the heat lost by the pan is equal to the heat gained by the water. The exchange of heat stops once a thermal equilibrium between the pan and the water is achieved. The heat exchange can be written as ∣ Q hot ∣ = Q cold .
If the area to which a force is applied is smaller then the pressure will be?	the same	equal	lower	greater	Pressure shows how concentrated the force is on a given area. The smaller the area to which force is applied, the greater the pressure is. Think about pressing a pushpin, like the one in the Figure below , into a bulletin board. You apply force with your thumb to the broad head of the pushpin. However, the force that the pushpin applies to the bulletin board acts only over the tiny point of the pin. This is a much smaller area, so the pressure the point applies to the bulletin board is much greater than the pressure you apply with your thumb. As a result, the pin penetrates the bulletin board with ease.
What do you call the preserved remains or traces of organisms that lived in the past?	decomposition	skulls	corals	fossils	Fossils are preserved remains or traces of organisms that lived in the past. Most preserved remains are hard parts, such as teeth, bones, or shells. Hard parts are less likely to be destroyed before they can become fossils. Even so, a very tiny percentage of living things become fossils. These types of fossils are called body fossils ( Figure below , Figure below , and Figure below ).
What process do single cell organisms use to remove waste and get nutrients into their cell?	Measured	convection	filtration	diffusion	over a specific distance and limits the size that an individual cell can attain. If a cell is a single-celled microorganism, such as an amoeba, it can satisfy all of its nutrient and waste needs through diffusion. If the cell is too large, then diffusion is ineffective and the center of the cell does not receive adequate nutrients nor is it able to effectively dispel its waste. An important concept in understanding how efficient diffusion is as a means of transport is the surface to volume ratio. Recall that any three-dimensional object has a surface area and volume; the ratio of these two quantities is the surfaceto-volume ratio. Consider a cell shaped like a perfect sphere: it has a surface area of 4πr2, and a volume of (4/3)πr3. The surface-to-volume ratio of a sphere is 3/r; as the cell gets bigger, its surface to volume ratio decreases, making diffusion less efficient. The larger the size of the sphere, or animal, the less surface area for diffusion it possesses. The solution to producing larger organisms is for them to become multicellular. Specialization occurs in complex organisms, allowing cells to become more efficient at doing fewer tasks. For example, circulatory systems bring nutrients and remove waste, while respiratory systems provide oxygen for the cells and remove carbon dioxide from them. Other organ systems have developed further specialization of cells and tissues and efficiently control body functions. Moreover, surface-tovolume ratio applies to other areas of animal development, such as the relationship between muscle mass and cross-sectional surface area in supporting skeletons, and in the relationship between muscle mass and the generation of dissipation of heat.
Trees release what gas as a byproduct of photosynthesis, thereby facilitating human respiration?	nitrogen	methane	carbon dioxide	oxygen	Recall that trees release oxygen as a byproduct of photosynthesis. And you need oxygen to breathe. Do you know why? So your cells can perform cellular respiration and make ATP.
What kind of muscle cells have a single nucleus and are spindle-shaped?	skeletal muscle	cardiac muscle	liquid muscle	smooth muscle	10.8 Smooth Muscle Smooth muscle is found throughout the body around various organs and tracts. Smooth muscle cells have a single nucleus, and are spindle-shaped. Smooth muscle cells can undergo hyperplasia, mitotically dividing to produce new cells. The smooth cells are nonstriated, but their sarcoplasm is filled with actin and myosin, along with dense bodies in the sarcolemma to anchor the thin filaments and a network of intermediate filaments involved in pulling the sarcolemma toward the fiber’s middle, shortening it in the process. Ca++ ions trigger contraction when they are released from SR and enter through opened voltage-gated calcium channels. Smooth muscle contraction is initiated when the Ca++ binds to intracellular calmodulin, which then activates an enzyme called myosin kinase that phosphorylates myosin heads so they can form the cross-bridges with actin and then pull on the thin filaments. Smooth muscle can be stimulated by pacesetter cells, by the autonomic nervous system, by hormones, spontaneously, or by stretching. The fibers in some smooth muscle have latch-bridges, crossbridges that cycle slowly without the need for ATP; these muscles can maintain low-level contractions for long periods. Single-unit smooth muscle tissue contains gap junctions to synchronize membrane depolarization and contractions so that the muscle contracts as a single unit. Single-unit smooth muscle in the walls of the viscera, called visceral muscle, has a stress-relaxation response that permits muscle to stretch, contract, and relax as the organ expands. Multiunit smooth muscle cells do not possess gap junctions, and contraction does not spread from one cell to the next.
The cortical reaction has begun, initiating events that ensure that only one sperm nucleus enters where?	the sperm	the spore	the heart	the egg	null
What do the process of moving air into and out of the lungs better known as?	photosynthesis	bleeding	consuming	breathing	Breathing is the process of moving air into and out of the lungs. The process depends on a muscle called the diaphragm. This is a large, sheet-like muscle below the lungs. You can see it in Figure below .
Which kind of rocks contain felsic minerals, typically contain aluminum and sodium and are high in silica?	sedimentary	metamorphic	igneous	felsic igneous	Felsic igneous rocks contain felsic minerals. They typically contain aluminum and sodium; they are high in silica. Quartz and potassium feldspar are felsic minerals. Minerals and rocks with a composition in between mafic and felsic are called intermediate.
What are trees that lose their leaves during winter called?	coniferous	fruits	fungus	deciduous	trees that lose their leaves once a year.
Other than gametes, normal human cells have a total of how many chromosomes per cell?	23	36	33	46	Human Chromosomes. Human chromosomes are shown here arranged by size. Chromosome 1 is the largest, and chromosome 22 is the smallest. All normal human cells (except gametes) have two of each chromosome, for a total of 46 chromosomes per cell. Only one of each pair is shown here.
What are the simplest type of carbon-based compounds?	fossil fuels	organic compounds	inorganic compounds	hydrocarbons	Hydrocarbons are compounds that contain only carbon and hydrogen. Hydrocarbons are the simplest type of carbon-based compounds, but they can vary greatly in size. The smallest hydrocarbons have just one or two carbon atoms. The largest hydrocarbons may have thousands of carbon atoms.
Gametogenesis, the production of sperm and eggs, takes place through the process of this?	osmosis	mutations	gametes	meiosis	Gametogenesis (Spermatogenesis and Oogenesis) Gametogenesis, the production of sperm and eggs, takes place through the process of meiosis. During meiosis, two cell divisions separate the paired chromosomes in the nucleus and then separate the chromatids that were made during an earlier stage of the cell’s life cycle. Meiosis produces haploid cells with half of each pair of chromosomes normally found in diploid cells. The production of sperm is called spermatogenesis and the production of eggs is called oogenesis. Spermatogenesis.
What is the name of the roundworms digestive organ?	stomach	intestine	tube	gut	A roundworm has a complete digestive system, which includes both a mouth and an anus. This is a significant difference from the incomplete digestive system of flatworms. The roundworm digestive system also include a large digestive organ known as the gut. Digestive enzymes that start to break down food are produced here. There is no stomach, but there is an intestine which produces enzymes that help absorb nutrients. The last portion of the intestine forms a rectum, which expels waste through the anus.
Oxides contain one or two metal elements combined with what?	ethanol	nitrogen	carbon	oxygen	Earth’s crust contains a lot of oxygen. The oxygen combines with many other elements to create oxide minerals. Oxides contain one or two metal elements combined with oxygen. Oxides are different from silicates because they do not contain silicon. Many important metals are found as oxides. For example, hematite and magnetite are both oxides that contain iron. Hematite (Fe 2 O 3 ) has a ratio of two iron atoms to three oxygen atoms. Magnetite (Fe 3 O 4 ) has a ratio of three iron atoms to four oxygen atoms. Notice that the word “magnetite” contains the word “magnet”. Magnetite is a magnetic mineral.
What combine the spinal sensory and motor components with a sensory input that directly generates a motor response?	tissues	senses	shocks	reflexes	Reflexes Reflexes combine the spinal sensory and motor components with a sensory input that directly generates a motor response. The reflexes that are tested in the neurological exam are classified into two groups. A deep tendon reflex is commonly known as a stretch reflex, and is elicited by a strong tap to a tendon, such as in the knee-jerk reflex. A superficial reflex is elicited through gentle stimulation of the skin and causes contraction of the associated muscles. For the arm, the common reflexes to test are of the biceps, brachioradialis, triceps, and flexors for the digits. For the leg, the knee-jerk reflex of the quadriceps is common, as is the ankle reflex for the gastrocnemius and soleus. The tendon at the insertion for each of these muscles is struck with a rubber mallet. The muscle is quickly stretched, resulting in activation of the muscle spindle that sends a signal into the spinal cord through the dorsal root. The fiber synapses directly on the ventral horn motor neuron that activates the muscle, causing contraction. The reflexes are physiologically useful for stability. If a.
What type of evolution happens when two species evolve the same traits?	multiplicative	divergent	associated	convergent	Sometimes two species evolve the same traits. It happens because they live in similar habitats. This is called convergent evolution . Caribbean Anoles demonstrate this as well.
Which way does an electric charge always move from?	diagonally	low to high	like to like	higher to lower	An electric charge flows when it has electric potential energy due to its position in an electric field. An electric charge always moves spontaneously from a position of higher to lower potential energy.
What is the principal blood vessel through which blood leaves the heart in order to circulate around the body?	the pulmonary artery	the superior vena cava	the pulmonary vein	aorta	Example 12.3 Calculating Flow Speed and Vessel Diameter: Branching in the Cardiovascular System The aorta is the principal blood vessel through which blood leaves the heart in order to circulate around the body. (a) Calculate the average speed of the blood in the aorta if the flow rate is 5.0 L/min. The aorta has a radius of 10 mm. (b) Blood also flows through smaller blood vessels known as capillaries. When the rate of blood flow in the aorta is 5.0 L/min, the speed of blood in the capillaries is about 0.33 mm/s. Given that the average diameter of a capillary is 8.0 µm , calculate the number of capillaries in the blood circulatory system. Strategy We can use.
What increases when a muscle like a biceps is extended?	momentum	weight	speed	force	In the above example of the biceps muscle, the angle between the forearm and upper arm is 90°. If this angle changes, the force exerted by the biceps muscle also changes. In addition, the length of the biceps muscle changes. The force the biceps muscle can exert depends upon its length; it is smaller when it is shorter than when it is stretched. Very large forces are also created in the joints. In the previous example, the downward force.
Hot magma beneath the surface mixes with water and forms what?	lava	hydrocarbons	liquids	gas	An explosive eruption produces huge clouds of volcanic ash. Chunks of the volcano fly high into the atmosphere. Explosive eruptions can be 10,000 times as powerful as an atomic bomb ( Figure below ). Hot magma beneath the surface mixes with water. This forms gases. The gas pressure grows until it must be released. The volcano erupts in an enormous explosion.
The olfactory receptor neurons are located in a small region within what cavity?	inferior nasal	exterior nasal	posterior nasal	superior nasal	Olfaction (Smell) Like taste, the sense of smell, or olfaction, is also responsive to chemical stimuli. The olfactory receptor neurons are located in a small region within the superior nasal cavity (Figure 14.4). This region is referred to as the olfactory epithelium and contains bipolar sensory neurons. Each olfactory sensory neuron has dendrites that extend from the apical surface of the epithelium into the mucus lining the cavity. As airborne molecules are inhaled through the nose, they pass over the olfactory epithelial region and dissolve into the mucus. These odorant molecules bind to proteins that keep them dissolved in the mucus and help transport them to the olfactory dendrites. The odorant–protein complex binds to a receptor protein within the cell membrane of an olfactory dendrite. These receptors are G protein–coupled, and will produce a graded membrane potential in the olfactory neurons. The axon of an olfactory neuron extends from the basal surface of the epithelium, through an olfactory foramen in the cribriform plate of the ethmoid bone, and into the brain. The group of axons called the olfactory tract connect to the olfactory bulb on the ventral surface of the frontal lobe. From there, the axons split to travel to several brain regions. Some.
Single bonds between atoms are always what?	analogue bonds	genetic bonds	rna bonds	sigma bonds	In general, single bonds between atoms are always sigma bonds. Double bonds are comprised of one sigma and one pi bond. Triple bonds are comprised of one sigma bond and two pi bonds.
What kind of attraction does electrical force have?	positive	similar	neutral	negative	The electrical force is a vector quantity that is positive in repulsion and negative in attraction.
At what temperatures do alkanes with more carbon atoms boil?	farther temperatures	heavier temperatures	lower temperatures	higher temperatures	Saturated hydrocarbons are given the general name of alkanes . The name of specific alkanes always ends in – ane . The first part of the name indicates how many carbon atoms each molecule of the alkane has. The smallest alkane is methane. It has just one carbon atom. The next largest is ethane with two carbon atoms. The chemical formulas and properties of methane, ethane, and other small alkanes are listed in the Table below . The boiling and melting points of alkanes are determined mainly by the number of carbon atoms they have. Alkanes with more carbon atoms generally boil and melt at higher temperatures.
If the tunica externa did not hold a vessel in place, any movement would likely result in disruption of what?	heart beat	respiration	pulse	blood flow	Tunica Externa The outer tunic, the tunica externa (also called the tunica adventitia), is a substantial sheath of connective tissue composed primarily of collagenous fibers. Some bands of elastic fibers are found here as well. The tunica externa in veins also contains groups of smooth muscle fibers. This is normally the thickest tunic in veins and may be thicker than the tunica media in some larger arteries. The outer layers of the tunica externa are not distinct but rather blend with the surrounding connective tissue outside the vessel, helping to hold the vessel in relative position. If you are able to palpate some of the superficial veins on your upper limbs and try to move them, you will find that the tunica externa prevents this. If the tunica externa did not hold the vessel in place, any movement would likely result in disruption of blood flow.
One common way to remove phosphates from water is by the addition of what?	isotopes	acetic acid	nitrous oxide	calcium hydroxide	One common way to remove phosphates from water is by the addition of calcium hydroxide, known as lime, Ca(OH)2. The lime is converted into calcium carbonate, a strong base, in the water. As the water is made more basic, the calcium ions react with phosphate ions to produce hydroxylapatite, Ca5(PO4)3(OH), which then precipitates out of the solution:.
Before going into hibernation bears eat constantly for what reason?	Decrease body protein	Decrease body fat	Increase body protein	increase body fat	null
What two elements make up about 99 percent of the air?	phosphorus and oxygen	nitrogen and phosphorus	helium and boron	nitrogen and oxygen	Nitrogen and oxygen make up about 99 percent of the air. Argon and carbon dioxide make up much of the rest. The air also contains water vapor. The amount of water vapor varies from place to place.
The different types of nuclei are referred to as what?	rhizomes	organelles	atoms	nuclides	Although the hydrogen nucleus consists of a single proton, the nuclei of all other elements contain both neutrons and protons. The different types of nuclei are referred to as nuclides . The number of protons in a nucleus is called the atomic number and is designated by the symbol . The total number of nucleons, neutrons and protons, is designated by the symbol and is called the mass number . A nuclide with 7 protons and 8 neutrons thus has and . The number of neutrons, , is . To specify a given nuclide, we need give only and . These can be shown in a complete nuclear symbol which takes the form.
What measure is the total mass of organisms at a trophic level?	phosphorus	detritus	atomic mass	biomass	Biomass is the total mass of organisms at a trophic level. With less energy at higher trophic levels, there are usually fewer organisms as well. This is also represented in the pyramid in Figure above . Organisms tend to be larger in size at higher trophic levels. However, their smaller numbers result in less biomass.
What has the least amount of energy in an atom?	rings	crystals	protons	electrons	The model in the Figure below shows the first four energy levels of an atom. Electrons in energy level I (also called energy level K) have the least amount of energy. As you go farther from the nucleus, electrons at higher levels have more energy, and their energy increases by a fixed, discrete amount. Electrons can jump from a lower to the next higher energy level if they absorb this amount of energy. Conversely, if electrons jump from a higher to a lower energy level, they give off energy, often in the form of light. This explains the fireworks pictured above. When the fireworks explode, electrons gain energy and jump to higher energy levels. When they jump back to their original energy levels, they release the energy as light. Different atoms have different arrangements of electrons, so they give off light of different colors. You can see an animation of electrons jumping from one energy level to another at this URL: http://cas. sdss. org/dr6/en/proj/advanced/spectraltypes/energylevels. asp .
What is the visible surface of the sun called?	ionosphere	chronosphere	stratosphere	photosphere	The photosphere is the visible surface of the Sun ( Figure below ). It's the part that we see shining. Surprisingly, the photosphere is also one of the coolest layers of the Sun. It is only about 6,000°C.
What do you call organisms that store chemical energy in carbohydrate food molecules they produce themselves?	heterotrophs	plants	omnivores	autotrophs	Autotrophs, shown in the Figure below , store chemical energy in carbohydrate food molecules they produce themselves. Food is chemical energy stored in organic molecules. Food provides both the energy to do work and the carbon to build the organic structures from cells to organisms. Because most autotrophs transform sunlight to make or synthesize food, we call the process they use photosynthesis . The food produced via this process is glucose. Only three groups of organisms - plants, algae, and some bacteria - are capable of this life-giving energy transformation. Autotrophs make food for their own use, but they make enough to support other life as well. Almost all other organisms depend absolutely on these three groups for the food they produce. The producers , as autotrophs are also known, begin food chains which feed all life. Food chains will be discussed in the Ecology concepts.
Which condition is the only autosomal trisomy where an affected individual may survive to adulthood?	type 1 diabetes	dwarfism	progeria	down syndrome	One of the most common chromosome abnormalities is Down syndrome , due to nondisjunction of chromosome 21 resulting in an extra complete chromosome 21, or part of chromosome 21 ( Figure below ). Down syndrome is the only autosomal trisomy where an affected individual may survive to adulthood. Individuals with Down syndrome often have some degree of mental retardation, some impairment of physical growth, and a specific facial appearance. With proper assistance, individuals with Down syndrome can become successful, contributing members of society. The incidence of Down syndrome increases with maternal age. The risk of having a child with Down syndrome is significantly higher among women age 35 and older.
What occurs when a population reaches the carrying capacity?	core stops	impact stops	growth increases	growth stops	A population can’t keep growing bigger and bigger forever. Sooner or later, it will run out of things it needs. For a given species, there is a maximum population that can be supported by the environment. This maximum is called the carrying capacity . When a population gets close to the carrying capacity, it usually grows more slowly. You can see this in Figure below . When the population reaches the carrying capacity, it stops growing.
What is the form of logical thinking that uses related observations to arrive at a general conclusion called?	deductive logic	hypthetical thinking	theory reasoning	inductive reasoning	There is no complete agreement when it comes to defining what the natural sciences include. For some experts, the natural sciences are astronomy, biology, chemistry, earth science, and physics. Other scholars choose to divide natural sciences into life sciences, which study living things and include biology, and physical sciences, which study nonliving matter and include astronomy, physics, and chemistry. Some disciplines such as biophysics and biochemistry build on two sciences and are interdisciplinary. Scientific Inquiry One thing is common to all forms of science: an ultimate goal “to know. ” Curiosity and inquiry are the driving forces for the development of science. Scientists seek to understand the world and the way it operates. Two methods of logical thinking are used: inductive reasoning and deductive reasoning. Inductive reasoning is a form of logical thinking that uses related observations to arrive at a general conclusion. This type of reasoning is common in descriptive science. A life scientist such as a biologist makes observations and records them.
Carbon can form single, double, or triple what with other carbon atoms	electron bonds	ionic bonds	phenotype bonds	covalent bonds	Carbon can form single, double, or triple covalent bonds with other carbon atoms.
Wind or water that travels toward the poles from the equator curves in which direction?	upward	west	downward	east	As wind or an ocean current moves, the Earth spins underneath it. Wind or water that travels toward the poles from the Equator curves to the east. Wind or water that travels toward the Equator from the poles curves to the west. The Coriolis effect bends the direction of surface currents to the right in the Northern Hemisphere. The currents curve left in the Southern Hemisphere ( Figure below ).
What is defined as the ability to cause changes in matter?	transcription	pressure	fuel	energy	The human ear is pictured below ( Figure below ). As you read about it, trace the path of sound waves through the ear. Assume a car horn blows in the distance. Sound waves spread through the air from the horn. Some of the sound waves reach your ear. The steps below show what happens next. They explain how your ears sense the sound.
Some spindle microtubules attach to the kinetochores of chromosomes and move the chromosomes to what plate?	prophase plate	boundary plate	interstitium plate	metaphase plate	null
What do plants use to make food for themselves and most other organisms?	gravity	heat	electricity	light	Visible light includes all the wavelengths of light that the human eye can detect. Humans and virtually all other organisms depend on visible light to survive. Humans and many other animals use it to see. Plants use it to make food for themselves and most other organisms.
Chlorophylls and carotenoids are the two major classes of pigments associated with what process and found in plants and algae?	glycolysis	mitosis	osmosis	photosynthesis	Understanding Pigments Different kinds of pigments exist, and each has evolved to absorb only certain wavelengths (colors) of visible light. Pigments reflect or transmit the wavelengths they cannot absorb, making them appear in the corresponding color. Chlorophylls and carotenoids are the two major classes of photosynthetic pigments found in plants and algae; each class has multiple types of pigment molecules. There are five major chlorophylls: a, b, c and d and a related molecule found in prokaryotes called bacteriochlorophyll. Chlorophyll a and chlorophyll b are found in higher plant chloroplasts and will be the focus of the following discussion. With dozens of different forms, carotenoids are a much larger group of pigments. The carotenoids found in fruit—such as the red of tomato (lycopene), the yellow of corn seeds (zeaxanthin), or the orange of an orange peel (β-carotene)—are used as advertisements to attract seed dispersers. In photosynthesis, carotenoids function as photosynthetic pigments that are very efficient molecules for the disposal of excess energy. When a leaf is exposed to full sun, the light-dependent reactions are required to process an enormous amount of energy; if that energy is not handled properly, it can do significant damage. Therefore, many carotenoids reside in the thylakoid membrane, absorb excess energy, and safely dissipate that energy as heat. Each type of pigment can be identified by the specific pattern of wavelengths it absorbs from visible light, which is the absorption spectrum. The graph in Figure 8.13 shows the absorption spectra for chlorophyll a, chlorophyll b, and a type of carotenoid pigment called β-carotene (which absorbs blue and green light). Notice how each pigment has a distinct set of peaks and troughs, revealing a highly specific pattern of absorption. Chlorophyll a absorbs wavelengths from either end of the visible spectrum (blue and red), but not green. Because green is reflected or transmitted, chlorophyll appears green. Carotenoids absorb in the short-wavelength blue region, and reflect the longer yellow, red, and orange wavelengths.
What is created when you combine simple machines?	digital devices	motors	factories	compound machines	Compound machines such as a wheelbarrow or corkscrew consist of just two simple machines. Big compound machines such as cars consist of hundreds or thousands of simple machines.
What is the general term for a parasite that causes disease ?	avian parasite	predator parasite	noxious parasite	pathogenic parasite	Bacteria: Friend or Foe? at http://biology. about. com/cs/bacteriology/a/aa032504a. htm .
What device measures atmospheric pressure and can be used as an altimeter?	indicator	thermometer	speedometer	barometer	A barometer is a device that measures atmospheric pressure. A mercury barometer is shown in Figure 11.18. This device measures atmospheric pressure, rather than gauge pressure, because there is a nearly pure vacuum above the mercury in the tube. The height of the mercury is such that hρg = P atm . When atmospheric pressure varies, the mercury rises or falls, giving important clues to weather forecasters. The barometer can also be used as an altimeter, since average atmospheric pressure varies with altitude. Mercury barometers and manometers are so common that units of mm Hg are often quoted for atmospheric pressure and blood pressures. Table 11.2 gives conversion factors for some of the more commonly used units of pressure.
What are solid-solid solutions like brass and bronze called?	amalgams	oxides	mixtures	alloys	Solid-solid solutions such as brass, bronze, and sterling silver are called alloys. Bronze (composed mainly of copper with added tin) was widely used in making weapons in times past dating back to at least 2400 B. C. This metal alloy was hard and tough, but was eventually replaced by iron.
What is the main element in organic compounds?	hydrogen	oxygen	helium	carbon	A compound found mainly in living things is known as an organic compound . Organic compounds make up the cells and other structures of organisms and carry out life processes. Carbon is the main element in organic compounds, so carbon is essential to life on Earth. Without carbon, life as we know it could not exist.
In living systems, diffusion of substances into and out of cells is mediated by the what?	battery membrane	cells membrane	Plant membrane	plasma membrane	3.5 Passive Transport The passive forms of transport, diffusion and osmosis, move material of small molecular weight. Substances diffuse from areas of high concentration to areas of low concentration, and this process continues until the substance is evenly distributed in a system. In solutions of more than one substance, each type of molecule diffuses according to its own concentration gradient. Many factors can affect the rate of diffusion, including concentration gradient, the sizes of the particles that are diffusing, and the temperature of the system. In living systems, diffusion of substances into and out of cells is mediated by the plasma membrane. Some materials diffuse readily through the membrane, but others are hindered, and their passage is only made possible by protein channels and carriers. The chemistry of living things occurs in aqueous solutions, and balancing the concentrations of those solutions is an ongoing problem. In living systems, diffusion of some substances would be slow or difficult without membrane proteins.
Desertification can result from slash-and-burn agriculture, which causes loss of what?	sediment	fertilizer	subsoil	topsoil	Slash-and-burn agriculture can lead to desertification, meaning the fertile top soil is lost.
What are certain numbers of nucleons, known as magic numbers stable against?	half-lifes	water	radiation	nuclear decay	certain numbers of nucleons, known as magic numbers, are stable against nuclear decay. These numbers of protons or neutrons (2, 8, 20, 28, 50, 82, and 126) make complete shells in the nucleus. These are similar in concept to the stable electron shells observed for the noble gases. Nuclei that have magic numbers of both protons and neutrons, such as 42 He, 168 O, 40 and 208 are called “double magic” and are particularly stable. These trends in 20 Ca, 82 Pb, nuclear stability may be rationalized by considering a quantum mechanical model of nuclear energy states analogous to that used to describe electronic states earlier in this textbook. The details of this model are beyond the scope of this chapter. Stable Nuclear Isotopes Number of Stable Isotopes.
Electron capture occurs when an inner shell electron combines with a proton and is converted into what?	protein	nuclei	photon	neutron	Figure 12.4 An overhead view of a car passing a truck on a highway. Air passing between the vehicles flows in a narrower channel and must increase its speed ( v 2 is greater than v 1 ), causing the pressure between them to drop ( P i is less than P o ). Greater pressure on the outside pushes the car and truck together.
What system consists of neurons that carry signals to skeletal muscles?	circulatory system	nervous system	endocrine system	motor system	null
Cross-pollination—or out-crossing—leads to greater genetic diversity because the microgametophyte and megagametophyte are derived from what?	dead plants	the same species	the same plant	different plants	Explore this interactive website (http://openstaxcollege. org/l/pollination) to review self-pollination and crosspollination. Living species are designed to ensure survival of their progeny; those that fail become extinct. Genetic diversity is therefore required so that in changing environmental or stress conditions, some of the progeny can survive. Self-pollination leads to the production of plants with less genetic diversity, since genetic material from the same plant is used to form gametes, and eventually, the zygote. In contrast, cross-pollination—or out-crossing—leads to greater genetic diversity because the microgametophyte and megagametophyte are derived from different plants. Because cross-pollination allows for more genetic diversity, plants have developed many ways to avoid self-pollination. In some species, the pollen and the ovary mature at different times. These flowers make self-pollination nearly impossible. By the time pollen matures and has been shed, the stigma of this flower is mature and can only be pollinated by pollen from another flower. Some flowers have developed physical features that prevent self-pollination. The primrose is one such flower. Primroses have evolved two flower types with differences in anther and stigma length: the pin-eyed flower has anthers positioned at the pollen tube’s halfway point, and the thrum-eyed flower’s stigma is likewise located at the halfway point. Insects easily cross-pollinate while seeking the nectar at the bottom of the pollen tube. This phenomenon is also known as heterostyly. Many plants, such as cucumber, have male and female flowers located on different parts of the plant, thus making self-pollination difficult. In yet other species, the male and female flowers are borne on different plants (dioecious). All of these are barriers to self-pollination; therefore, the plants depend on pollinators to transfer pollen. The majority of pollinators are biotic agents such as insects (like bees, flies, and butterflies), bats, birds, and other animals. Other plant species are pollinated by abiotic agents, such as wind and water.
Cancers are caused by a series of what?	microbes	adaptations	parasites	mutations	Cancers are caused by a series of mutations. Each mutation alters the behavior of the cell. In this example, the first mutation inactivates a tumor suppressor gene, the second mutation inactivates a DNA repair gene, the third mutation creates an oncogene, and a fourth mutation inactivates several more tumor suppressor genes, resulting in cancer. It should be noted that it does not necessarily require four or more mutations to lead to cancer.
In comparison to light, the speed of sound is faster or slower?	sound does does not travel	faster	the same	slower	Figure 17.8 When a firework explodes, the light energy is perceived before the sound energy. Sound travels more slowly than light does. (credit: Dominic Alves, Flickr).

Animals use saturated fatty acids to store what?

water

blood

hydrogen

energy

Animals use saturated fatty acids to store energy. Plants use unsaturated fatty acids to store energy.

The atmospheric concentration of carbon dioxide on earth has been regulated by the concentration of what form of life?

seaweed

fruit

fungus

plant

Homeostasis is a term that is also used when talking about the environment. For example, the atmospheric concentration of carbon dioxide on Earth has been regulated by the concentration of plant life on Earth, because plants remove more carbon dioxide from the atmosphere during the daylight hours than they emit to the atmosphere at night.

What organisms have a life cycle that includes alternation of generations?

insects

fungi

animals

plants

All plants have a characteristic life cycle that includes alternation of generations.

What are nekton animals able to do in water?

reproduce

breath

lay eggs

move on their own, swim

Nekton are aquatic animals that can move on their own by “swimming” through the water. They may live in the photic or aphotic zone. They feed on plankton or other nekton. Examples of nekton include fish and shrimp.

What is a property of a system whose magnitude depends on only the present state of the system, not its previous history?

intensive function

extensive function

laplacian

state function

conserved. The state of a system is a complete description of a system at a given time, including its temperature and pressure, the amount of matter it contains, its chemical composition, and the physical state of the matter. A state function is a property of a system whose magnitude depends on only the present state of the system, not its previous history. Temperature, pressure, volume, and potential energy are all state functions. The temperature of an oven, for example, is independent of however many steps it may have taken for it to reach that temperature. Similarly, the pressure in a tire is independent of how often air is pumped into the tire for it to reach that pressure, as is the final volume of air in the tire. Heat and work, on the other hand, are not state functions because they are path dependent. For example, a car sitting on the top level of a parking garage has the same potential energy whether it was lifted by a crane, set there by a helicopter, driven up, or pushed up by a group of students (). The amount of work expended to get it there, however, can differ greatly depending on the path chosen. If the students decided to carry the car to the top of the ramp, they would perform a great deal more work than if they simply pushed the car up the ramp (unless, of course, they neglected to release the parking brake, in which case the work expended would increase substantially!). The potential energy of the car is the same, however, no matter which path they choose.

Prokaryotic cells lack what key structure and other membrane-bound organelles?

proton

cell wall

epidermis

nucleus

Prokaryotic cells lack a nucleus and other membrane-bound organelles.

All of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as what?

particles ' s metabolism

slowed metabolism

genetic metabolism

cell ' s metabolism

4.1 | Energy and Metabolism By the end of this section, you will be able to: • Explain what metabolic pathways are • State the first and second laws of thermodynamics • Explain the difference between kinetic and potential energy • Describe endergonic and exergonic reactions • Discuss how enzymes function as molecular catalysts Scientists use the term bioenergetics to describe the concept of energy flow (Figure 4.2) through living systems, such as cells. Cellular processes such as the building and breaking down of complex molecules occur through stepwise chemical reactions. Some of these chemical reactions are spontaneous and release energy, whereas others require energy to proceed. Just as living things must continually consume food to replenish their energy supplies, cells must continually produce more energy to replenish that used by the many energy-requiring chemical reactions that constantly take place. Together, all of the chemical reactions that take place inside cells, including those that consume or generate energy, are referred to as the cell’s metabolism.

In genetic drift, chance fluctuations in allele frequencies over generations tend to reduce what?

genetic entanglement

biochemical variation

responsible variation

genetic variation

null

What gives the order of electron filling in an atom?

periodic table

orbit order

Bohr's law

aufbau principle

The Aufbau principle gives the order of electron filling in an atom.

What occurs whenever an unbalanced force acts on an object?

vibration

compression

inertia

acceleration

Whenever an object speeds up, slows down, or changes direction, it accelerates. Acceleration occurs whenever an unbalanced force acts on an object. Two factors affect the acceleration of an object: the net force acting on the object and the object’s mass. Newton’s second law of motion describes how force and mass affect acceleration. The law states that the acceleration of an object equals the net force acting on the object divided by the object’s mass. This can be represented by the equation:.

What are large collections of millions or billions of stars called?

orbits

fragments

universe

galaxies

Galaxies are collections of millions to many billions of stars.

What is the developmental process of gastropods called?

occlusion

regeneration

modulation

torsion

null

Name one unit used to measure pressure.

decibel

watt

meter

torr

Pressures are given in a multitude of units. We've already discussed Pascals, and we know that another unit for pressure is the atmosphere (1 atm = 101.3 x 10 5 Pa). The third commonly used pressure unit is the torr (symbol: Torr). 760 torr is 1 atm, but 1 torr is also the increase in pressure necessary to cause liquid mercury to rise by 1 mm. For that reason, torr is also commonly referred to as "millimeters mercury. " Another pressure unit commonly used in our everyday world is psi, or pounds per square inch, though neither psi nor torr are SI units.

Eggs and sperm are not somatic cells but instead what kind of cells?

Sickness

toxins

pollen

germ

So far in this chapter, you have read numerous times of the importance and prevalence of cell division. While there are a few cells in the body that do not undergo cell division (such as gametes, red blood cells, most neurons, and some muscle cells), most somatic cells divide regularly. A somatic cell is a general term for a body cell, and all human cells, except for the cells that produce eggs and sperm (which are referred to as germ cells), are somatic cells. Somatic cells contain two copies of each of their chromosomes (one copy received from each parent). A homologous pair of chromosomes is the two copies of a single chromosome found in each somatic cell. The human is a diploid organism, having 23 homologous pairs of chromosomes in each of the somatic cells. The condition of having pairs of chromosomes is known as diploidy. Cells in the body replace themselves over the lifetime of a person. For example, the cells lining the gastrointestinal tract must be frequently replaced when constantly “worn off” by the movement of food through the gut. But what triggers a cell to divide, and how does it prepare for and complete cell division? The cell cycle is the sequence of events in the life of the cell from the moment it is created at the end of a previous cycle of cell division until it then divides itself, generating two new cells.

Regular checkups with what type of specialist can detect skin cancers early?

internist

endocrinologist

nephrologist

dermatologist

Regular checkups with a dermatologist can detect skin cancers early. Why is early detection important?.

Receptors for what sense are located within sensory hairs on the feet of insects, as well as in mouthparts?

smell

touch

sight

taste

null

Where does the stored energy in fossil fuels originally come from, before it changed forms several times?

decomposers

the Moon

Earth's core

the sun

Fossil fuels contain stored chemical energy that came originally from the sun. Ancient plants changed energy in sunlight to stored chemical energy in food, which was eaten by other organisms. After the plants and other organisms died, their remains gradually changed to fossil fuels as they were pressed beneath layers of sediments. Petroleum and natural gas formed from marine organisms and are often found together. Coal formed from giant tree ferns and other swamp plants.

A prokaryote is a simple, mostly single-celled organism that lacks what key organelle?

ribosome

chloroplast

golgi apparatus

nucleus

are found; 3) DNA, the genetic material of the cell; and 4) ribosomes, which synthesize proteins. However, prokaryotes differ from eukaryotic cells in several ways. A prokaryote is a simple, mostly single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle. We will shortly come to see that this is significantly different in eukaryotes. Prokaryotic DNA is found in a central part of the cell: the nucleoid (Figure 4.5).

Increasing the surface area of solid reactants increases what rate?

breathing

fusion

metabolism

reaction

When a solid substance is involved in a chemical reaction, only the matter at the surface of the solid is exposed to other reactants. If a solid has more surface area, more of it is exposed and able to react. Therefore, increasing the surface area of solid reactants increases the reaction rate. Look at the hammer and nails pictured in the Figure below . Both are made of iron and will rust when the iron combines with oxygen in the air. However, the nails have a greater surface area, so they will rust faster.

Epithelial cells are found in what body organ?

liver

lungs

brain

skin

DNA Replication In order for an organism to grow, develop, and maintain its health, cells must reproduce themselves by dividing to produce two new daughter cells, each with the full complement of DNA as found in the original cell. Billions of new cells are produced in an adult human every day. Only very few cell types in the body do not divide, including nerve cells, skeletal muscle fibers, and cardiac muscle cells. The division time of different cell types varies. Epithelial cells of the skin and gastrointestinal lining, for instance, divide very frequently to replace those that are constantly being rubbed off of the surface by friction. A DNA molecule is made of two strands that “complement” each other in the sense that the molecules that compose the strands fit together and bind to each other, creating a double-stranded molecule that looks much like a long, twisted ladder. Each side rail of the DNA ladder is composed of alternating sugar and phosphate groups (Figure 3.23). The two sides of the.

What's the name for an organic compound in which halogen atoms are substituted for hydrogen in a hydrocarbon?

alcohol

sodium halide

glucose

alkyl halide

An alkyl halide is an organic compound in which one or more halogen atoms are substituted for one or more hydrogen atoms in a hydrocarbon. The general formulas for organic molecules with functional groups use the letter R to stand for the rest of the molecule outside of the functional group. Because there are four possible halogen atoms (fluorine, chlorine, bromine, or iodine) that can act as the functional group, we use the general formula R−X to represent an alkyl halide. The rules for naming simple alkyl halides are listed below.

The trachea and bronchi are made of incomplete rings of this?

ligaments

membrane

collagen

cartilage

Figure 39.8 The trachea and bronchi are made of incomplete rings of cartilage. (credit: modification of work by Gray's Anatomy).

What do we call cyclones that form in tropical latitudes?

eruptions

twister

disturbances

hurricanes

Hurricanes are cyclones that form in tropical latitudes. They are called tropical cyclones.

Which amino acid do organisms incorporate into their proteins?

glutamate

histone

peptide

arginine

null

What fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms?

trilobites

coal

sediment

fossil

Oil, or petroleum, is one of several fossil fuels . Fossil fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms. In addition to oil, they include coal and natural gas. Fossil fuels provide most of the energy used in the world today. They are burned in power plants to produce electrical energy, and they also fuel cars, heat homes, and supply energy for many other purposes. You can see some ways they are used in the Figure below . For a more detailed introduction to fossil fuels, go to this URL: http://www. ecokids. ca/pub/eco_info/topics/energy/ecostats/index. cfm.

What is the cartilaginous structure that extends from the pharynx to the primary bronchi?

sternohyoid

larynx

cricoid

trachea

Chapter 39 1 Figure 39.7 B 3 Figure 39.20 The blood pH will drop and hemoglobin affinity for oxygen will decrease. 4 A 6 B 8 D 10 B 12 D 14 C 16 The main bronchus is the conduit in the lung that funnels air to the airways where gas exchange occurs. The main bronchus attaches the lungs to the very end of the trachea where it bifurcates. The trachea is the cartilaginous structure that extends from the pharynx to the primary bronchi. It serves to funnel air to the lungs. The alveoli are the sites of gas exchange; they are located at the terminal regions of the lung and are attached to the respiratory bronchioles. The acinus is the structure in the lung where gas exchange occurs. 18 FEV1/FVC measures the forced expiratory volume in one second in relation to the total forced vital capacity (the total amount of air that is exhaled from the lung from a maximal inhalation). This ratio changes with alterations in lung function that arise from diseases such as fibrosis, asthma, and COPD. 20 Oxygen moves from the lung to the bloodstream to the tissues according to the pressure gradient. This is measured as the partial pressure of oxygen. If the amount of oxygen drops in the inspired air, there would be reduced partial pressure. This would decrease the driving force that moves the oxygen into the blood and into the tissues. P O is also reduced at high elevations: P O at high elevations is lower than 2.

Excess dietary fat is stored as triglycerides in the body. what type of tissue is used to store the triglycerides?

metabolic

connective

muscle

adipose

inside these cells, glucose is immediately converted into glucose-6-phosphate. By doing this, a concentration gradient is established where glucose levels are higher in the blood than in the cells. This allows for glucose to continue moving from the blood to the cells where it is needed. Insulin also stimulates the storage of glucose as glycogen in the liver and muscle cells where it can be used for later energy needs of the body. Insulin also promotes the synthesis of protein in muscle. As you will see, muscle protein can be catabolized and used as fuel in times of starvation. If energy is exerted shortly after eating, the dietary fats and sugars that were just ingested will be processed and used immediately for energy. If not, the excess glucose is stored as glycogen in the liver and muscle cells, or as fat in adipose tissue; excess dietary fat is also stored as triglycerides in adipose tissues. Figure 24.21 summarizes the metabolic processes occurring in the body during the absorptive state.

What do you call winds that occur in belts that go all around the planet?

solar winds

rotational winds

gravitational winds

global winds

Global winds are winds that occur in belts that go all around the planet. You can see them in Figure below . Like local winds, global winds are caused by unequal heating of the atmosphere.

What property is a property that depends on the amount of matter in a sample?

non-exact

provided

relative

extensive

Some properties of matter depend on the size of the sample, while some do not. An extensive property is a property that depends on the amount of matter in a sample. The mass of an object is a measure of the amount of matter that an object contains. A small sample of a certain type of matter will have a small mass, while a larger sample will have a greater mass. Another extensive property is volume . The volume of an object is a measure of the space that is occupied by that object.

The legend explains features and symbols on?

earth

telescopes

compass

map

Look for the legend on the top left side of the map. The legend explains other features and symbols on the map.

Organic acids such as acetic acid all contain a functional group called what?

ester group

glycoprotein group

protein

carboxyl group

Organic acids such as acetic acid all contain a functional group called a carboxyl group .

Which is the only organ system in humans that differs greatly between males and females?

neural system

digestive system

immune system

reproductive system

Dogs have puppies. Cats have kittens. All organisms reproduce, obviously including humans. Like other mammals, humans have a body system that controls reproduction. It is called the reproductive system . It is the only human body system that is very different in males and females. The male and female reproductive systems have different organs and different functions.

Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the what membrane?

mucous

cutaneous

serous

tympanic

Figure 36.13 Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the tympanic membrane. The middle ear contains three bones called ossicles that transfer the sound wave to the oval window, the exterior boundary of the inner ear. The organ of Corti, which is the organ of sound transduction, lies inside the cochlea. (credit: modification of work by Lars Chittka, Axel Brockmann).

What is the most common cause of hearing loss?

quiet sounds

birth defect

infection

loud sounds

Many activities expose people to dangerously loud sounds that can cause hearing loss.

Some products contain iron filings that will react with air to release what type of energy?

spectral

physical

mechanical

thermal

Hikers, campers, and other outdoor folks take advantage of chemical reactions to keep their hands warm. Small containers of chemicals can undergo reaction to generate heat that can be used to avoid frostbite. Some products contain iron filings that will react with air to release thermal energy. These types of warmer cannot be reused. Other systems rely on heat being released when certain chemicals crystallize. If the warmer is placed in very hot water after use, the system can be regenerated.

Mutations in what type of regulatory gene can cause misplacement of structures in an animal?

myogenic

dichotic

diploid

homeotic

null

By what processes do rivers create floodplains?

deposition and sedimentation

depletion and erosion

thrust and deposition

erosion and deposition

Erosion and deposition by slow-flowing rivers creates broad floodplains and meanders.

What biological agents that infect living hosts contain dna, yet lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes?

bacteria

parasites

worms

viruses

Viruses contain DNA but not much else. They lack the other parts shared by all cells, including a plasma membrane, cytoplasm, and ribosomes. Therefore, viruses are not cells, but are they alive? All living things not only have cells; they are also capable of reproduction. Viruses cannot reproduce by themselves. Instead, they infect living hosts, and use the hosts’ cells to make copies of their own DNA. Viruses also do not have their own metabolism or maintain homeostasis. For these reasons, most scientists do not consider viruses to be living things.

An extensive property is a property that depends on the amount of what in a sample?

water

plasma

space

matter

An extensive property is a property that depends on the amount of matter in a sample.

A wheel with a rope wrapped around it, hanging over a building, is an example of what type of machine?

simple machine

pedal

propeller

pulley

This rusty iron wheel has a rope wrapped around it. The wheel and rope hang over a building. Together they make up a type of machine called a pulley.

Early types of what animals were the first vertebrates that moved onto land and have true lungs, although they had to return to the water to reproduce?

reptiles

mammals

birds

amphibians

The first vertebrates moved onto land about 365 million years ago. They were early amphibians. They were the first animals to have true lungs and limbs for life on land. However, they still had to return to the water to reproduce. That’s because their eggs lacked a waterproof covering and would dry out on land.

Many heterocyclic amines occur naturally in what?

animals

gases

nuclei

plants

nucleic acids, which in turn compose the genetic material of cells and direct protein synthesis. (For more information about nucleic acids, see Chapter 19 "Nucleic Acids". ) Many heterocyclic amines occur naturally in plants. Like other amines, these compounds are basic. Such a compound is an alkaloid, a name that means “like alkalis. ” Many alkaloids are physiologically active, including the familiar drugs caffeine, nicotine, and cocaine.

What do wind turbines change the kinetic energy of the wind into?

transportable energy

potential energy

available energy

electrical energy

Wind is moving air, so it has kinetic energy that can do work. Remember the wind turbines that opened this chapter? Wind turbines change the kinetic energy of the wind to electrical energy. Only certain areas of the world get enough steady wind to produce much electricity. Many people also think that wind turbines are noisy and unattractive in the landscape.

Population growth depends on birth rates and death rates, as well as what?

marriage

industrialization

communication

migration

Population growth rate depends on birth rates and death rates, as well as migration. First, we will consider the effects of birth and death rates. You can predict the growth rate by using this simple equation: growth rate = birth rate – death rate.

The exchange of heat stops once what property of equilibrium between the pan and the water is achieved?

motion

density

viscosity

thermal

of 150ºC . Assume that the pan is placed on an insulated pad and that a negligible amount of water boils off. What is the temperature when the water and pan reach thermal equilibrium a short time later? Strategy The pan is placed on an insulated pad so that little heat transfer occurs with the surroundings. Originally the pan and water are not in thermal equilibrium: the pan is at a higher temperature than the water. Heat transfer then restores thermal equilibrium once the water and pan are in contact. Because heat transfer between the pan and water takes place rapidly, the mass of evaporated water is negligible and the magnitude of the heat lost by the pan is equal to the heat gained by the water. The exchange of heat stops once a thermal equilibrium between the pan and the water is achieved. The heat exchange can be written as ∣ Q hot ∣ = Q cold .

If the area to which a force is applied is smaller then the pressure will be?

the same

equal

lower

greater

Pressure shows how concentrated the force is on a given area. The smaller the area to which force is applied, the greater the pressure is. Think about pressing a pushpin, like the one in the Figure below , into a bulletin board. You apply force with your thumb to the broad head of the pushpin. However, the force that the pushpin applies to the bulletin board acts only over the tiny point of the pin. This is a much smaller area, so the pressure the point applies to the bulletin board is much greater than the pressure you apply with your thumb. As a result, the pin penetrates the bulletin board with ease.

What do you call the preserved remains or traces of organisms that lived in the past?

decomposition

skulls

corals

fossils

Fossils are preserved remains or traces of organisms that lived in the past. Most preserved remains are hard parts, such as teeth, bones, or shells. Hard parts are less likely to be destroyed before they can become fossils. Even so, a very tiny percentage of living things become fossils. These types of fossils are called body fossils ( Figure below , Figure below , and Figure below ).

What process do single cell organisms use to remove waste and get nutrients into their cell?

Measured

convection

filtration

diffusion

over a specific distance and limits the size that an individual cell can attain. If a cell is a single-celled microorganism, such as an amoeba, it can satisfy all of its nutrient and waste needs through diffusion. If the cell is too large, then diffusion is ineffective and the center of the cell does not receive adequate nutrients nor is it able to effectively dispel its waste. An important concept in understanding how efficient diffusion is as a means of transport is the surface to volume ratio. Recall that any three-dimensional object has a surface area and volume; the ratio of these two quantities is the surfaceto-volume ratio. Consider a cell shaped like a perfect sphere: it has a surface area of 4πr2, and a volume of (4/3)πr3. The surface-to-volume ratio of a sphere is 3/r; as the cell gets bigger, its surface to volume ratio decreases, making diffusion less efficient. The larger the size of the sphere, or animal, the less surface area for diffusion it possesses. The solution to producing larger organisms is for them to become multicellular. Specialization occurs in complex organisms, allowing cells to become more efficient at doing fewer tasks. For example, circulatory systems bring nutrients and remove waste, while respiratory systems provide oxygen for the cells and remove carbon dioxide from them. Other organ systems have developed further specialization of cells and tissues and efficiently control body functions. Moreover, surface-tovolume ratio applies to other areas of animal development, such as the relationship between muscle mass and cross-sectional surface area in supporting skeletons, and in the relationship between muscle mass and the generation of dissipation of heat.

Trees release what gas as a byproduct of photosynthesis, thereby facilitating human respiration?

nitrogen

methane

carbon dioxide

oxygen

Recall that trees release oxygen as a byproduct of photosynthesis. And you need oxygen to breathe. Do you know why? So your cells can perform cellular respiration and make ATP.

What kind of muscle cells have a single nucleus and are spindle-shaped?

skeletal muscle

cardiac muscle

liquid muscle

smooth muscle

10.8 Smooth Muscle Smooth muscle is found throughout the body around various organs and tracts. Smooth muscle cells have a single nucleus, and are spindle-shaped. Smooth muscle cells can undergo hyperplasia, mitotically dividing to produce new cells. The smooth cells are nonstriated, but their sarcoplasm is filled with actin and myosin, along with dense bodies in the sarcolemma to anchor the thin filaments and a network of intermediate filaments involved in pulling the sarcolemma toward the fiber’s middle, shortening it in the process. Ca++ ions trigger contraction when they are released from SR and enter through opened voltage-gated calcium channels. Smooth muscle contraction is initiated when the Ca++ binds to intracellular calmodulin, which then activates an enzyme called myosin kinase that phosphorylates myosin heads so they can form the cross-bridges with actin and then pull on the thin filaments. Smooth muscle can be stimulated by pacesetter cells, by the autonomic nervous system, by hormones, spontaneously, or by stretching. The fibers in some smooth muscle have latch-bridges, crossbridges that cycle slowly without the need for ATP; these muscles can maintain low-level contractions for long periods. Single-unit smooth muscle tissue contains gap junctions to synchronize membrane depolarization and contractions so that the muscle contracts as a single unit. Single-unit smooth muscle in the walls of the viscera, called visceral muscle, has a stress-relaxation response that permits muscle to stretch, contract, and relax as the organ expands. Multiunit smooth muscle cells do not possess gap junctions, and contraction does not spread from one cell to the next.

The cortical reaction has begun, initiating events that ensure that only one sperm nucleus enters where?

the sperm

the spore

the heart

the egg

null

What do the process of moving air into and out of the lungs better known as?

photosynthesis

bleeding

consuming

breathing

Breathing is the process of moving air into and out of the lungs. The process depends on a muscle called the diaphragm. This is a large, sheet-like muscle below the lungs. You can see it in Figure below .

Which kind of rocks contain felsic minerals, typically contain aluminum and sodium and are high in silica?

sedimentary

metamorphic

igneous

felsic igneous

Felsic igneous rocks contain felsic minerals. They typically contain aluminum and sodium; they are high in silica. Quartz and potassium feldspar are felsic minerals. Minerals and rocks with a composition in between mafic and felsic are called intermediate.

What are trees that lose their leaves during winter called?

coniferous

fruits

fungus

deciduous

trees that lose their leaves once a year.

Other than gametes, normal human cells have a total of how many chromosomes per cell?

23

36

33

46

Human Chromosomes. Human chromosomes are shown here arranged by size. Chromosome 1 is the largest, and chromosome 22 is the smallest. All normal human cells (except gametes) have two of each chromosome, for a total of 46 chromosomes per cell. Only one of each pair is shown here.

What are the simplest type of carbon-based compounds?

fossil fuels

organic compounds

inorganic compounds

hydrocarbons

Hydrocarbons are compounds that contain only carbon and hydrogen. Hydrocarbons are the simplest type of carbon-based compounds, but they can vary greatly in size. The smallest hydrocarbons have just one or two carbon atoms. The largest hydrocarbons may have thousands of carbon atoms.

Gametogenesis, the production of sperm and eggs, takes place through the process of this?

osmosis

mutations

gametes

meiosis

Gametogenesis (Spermatogenesis and Oogenesis) Gametogenesis, the production of sperm and eggs, takes place through the process of meiosis. During meiosis, two cell divisions separate the paired chromosomes in the nucleus and then separate the chromatids that were made during an earlier stage of the cell’s life cycle. Meiosis produces haploid cells with half of each pair of chromosomes normally found in diploid cells. The production of sperm is called spermatogenesis and the production of eggs is called oogenesis. Spermatogenesis.

What is the name of the roundworms digestive organ?

stomach

intestine

tube

gut

A roundworm has a complete digestive system, which includes both a mouth and an anus. This is a significant difference from the incomplete digestive system of flatworms. The roundworm digestive system also include a large digestive organ known as the gut. Digestive enzymes that start to break down food are produced here. There is no stomach, but there is an intestine which produces enzymes that help absorb nutrients. The last portion of the intestine forms a rectum, which expels waste through the anus.

Oxides contain one or two metal elements combined with what?

ethanol

nitrogen

carbon

oxygen

Earth’s crust contains a lot of oxygen. The oxygen combines with many other elements to create oxide minerals. Oxides contain one or two metal elements combined with oxygen. Oxides are different from silicates because they do not contain silicon. Many important metals are found as oxides. For example, hematite and magnetite are both oxides that contain iron. Hematite (Fe 2 O 3 ) has a ratio of two iron atoms to three oxygen atoms. Magnetite (Fe 3 O 4 ) has a ratio of three iron atoms to four oxygen atoms. Notice that the word “magnetite” contains the word “magnet”. Magnetite is a magnetic mineral.

What combine the spinal sensory and motor components with a sensory input that directly generates a motor response?

tissues

senses

shocks

reflexes

Reflexes Reflexes combine the spinal sensory and motor components with a sensory input that directly generates a motor response. The reflexes that are tested in the neurological exam are classified into two groups. A deep tendon reflex is commonly known as a stretch reflex, and is elicited by a strong tap to a tendon, such as in the knee-jerk reflex. A superficial reflex is elicited through gentle stimulation of the skin and causes contraction of the associated muscles. For the arm, the common reflexes to test are of the biceps, brachioradialis, triceps, and flexors for the digits. For the leg, the knee-jerk reflex of the quadriceps is common, as is the ankle reflex for the gastrocnemius and soleus. The tendon at the insertion for each of these muscles is struck with a rubber mallet. The muscle is quickly stretched, resulting in activation of the muscle spindle that sends a signal into the spinal cord through the dorsal root. The fiber synapses directly on the ventral horn motor neuron that activates the muscle, causing contraction. The reflexes are physiologically useful for stability. If a.

What type of evolution happens when two species evolve the same traits?

multiplicative

divergent

associated

convergent

Sometimes two species evolve the same traits. It happens because they live in similar habitats. This is called convergent evolution . Caribbean Anoles demonstrate this as well.

Which way does an electric charge always move from?

diagonally

low to high

like to like

higher to lower

An electric charge flows when it has electric potential energy due to its position in an electric field. An electric charge always moves spontaneously from a position of higher to lower potential energy.

What is the principal blood vessel through which blood leaves the heart in order to circulate around the body?

the pulmonary artery

the superior vena cava

the pulmonary vein

aorta

Example 12.3 Calculating Flow Speed and Vessel Diameter: Branching in the Cardiovascular System The aorta is the principal blood vessel through which blood leaves the heart in order to circulate around the body. (a) Calculate the average speed of the blood in the aorta if the flow rate is 5.0 L/min. The aorta has a radius of 10 mm. (b) Blood also flows through smaller blood vessels known as capillaries. When the rate of blood flow in the aorta is 5.0 L/min, the speed of blood in the capillaries is about 0.33 mm/s. Given that the average diameter of a capillary is 8.0 µm , calculate the number of capillaries in the blood circulatory system. Strategy We can use.

What increases when a muscle like a biceps is extended?

momentum

weight

speed

force

In the above example of the biceps muscle, the angle between the forearm and upper arm is 90°. If this angle changes, the force exerted by the biceps muscle also changes. In addition, the length of the biceps muscle changes. The force the biceps muscle can exert depends upon its length; it is smaller when it is shorter than when it is stretched. Very large forces are also created in the joints. In the previous example, the downward force.

Hot magma beneath the surface mixes with water and forms what?

lava

hydrocarbons

liquids

gas

An explosive eruption produces huge clouds of volcanic ash. Chunks of the volcano fly high into the atmosphere. Explosive eruptions can be 10,000 times as powerful as an atomic bomb ( Figure below ). Hot magma beneath the surface mixes with water. This forms gases. The gas pressure grows until it must be released. The volcano erupts in an enormous explosion.

The olfactory receptor neurons are located in a small region within what cavity?

inferior nasal

exterior nasal

posterior nasal

superior nasal

Olfaction (Smell) Like taste, the sense of smell, or olfaction, is also responsive to chemical stimuli. The olfactory receptor neurons are located in a small region within the superior nasal cavity (Figure 14.4). This region is referred to as the olfactory epithelium and contains bipolar sensory neurons. Each olfactory sensory neuron has dendrites that extend from the apical surface of the epithelium into the mucus lining the cavity. As airborne molecules are inhaled through the nose, they pass over the olfactory epithelial region and dissolve into the mucus. These odorant molecules bind to proteins that keep them dissolved in the mucus and help transport them to the olfactory dendrites. The odorant–protein complex binds to a receptor protein within the cell membrane of an olfactory dendrite. These receptors are G protein–coupled, and will produce a graded membrane potential in the olfactory neurons. The axon of an olfactory neuron extends from the basal surface of the epithelium, through an olfactory foramen in the cribriform plate of the ethmoid bone, and into the brain. The group of axons called the olfactory tract connect to the olfactory bulb on the ventral surface of the frontal lobe. From there, the axons split to travel to several brain regions. Some.

Single bonds between atoms are always what?

analogue bonds

genetic bonds

rna bonds

sigma bonds

In general, single bonds between atoms are always sigma bonds. Double bonds are comprised of one sigma and one pi bond. Triple bonds are comprised of one sigma bond and two pi bonds.

What kind of attraction does electrical force have?

positive

similar

neutral

negative

The electrical force is a vector quantity that is positive in repulsion and negative in attraction.

At what temperatures do alkanes with more carbon atoms boil?

farther temperatures

heavier temperatures

lower temperatures

higher temperatures

Saturated hydrocarbons are given the general name of alkanes . The name of specific alkanes always ends in – ane . The first part of the name indicates how many carbon atoms each molecule of the alkane has. The smallest alkane is methane. It has just one carbon atom. The next largest is ethane with two carbon atoms. The chemical formulas and properties of methane, ethane, and other small alkanes are listed in the Table below . The boiling and melting points of alkanes are determined mainly by the number of carbon atoms they have. Alkanes with more carbon atoms generally boil and melt at higher temperatures.

If the tunica externa did not hold a vessel in place, any movement would likely result in disruption of what?

heart beat

respiration

pulse

blood flow

Tunica Externa The outer tunic, the tunica externa (also called the tunica adventitia), is a substantial sheath of connective tissue composed primarily of collagenous fibers. Some bands of elastic fibers are found here as well. The tunica externa in veins also contains groups of smooth muscle fibers. This is normally the thickest tunic in veins and may be thicker than the tunica media in some larger arteries. The outer layers of the tunica externa are not distinct but rather blend with the surrounding connective tissue outside the vessel, helping to hold the vessel in relative position. If you are able to palpate some of the superficial veins on your upper limbs and try to move them, you will find that the tunica externa prevents this. If the tunica externa did not hold the vessel in place, any movement would likely result in disruption of blood flow.

One common way to remove phosphates from water is by the addition of what?

isotopes

acetic acid

nitrous oxide

calcium hydroxide

One common way to remove phosphates from water is by the addition of calcium hydroxide, known as lime, Ca(OH)2. The lime is converted into calcium carbonate, a strong base, in the water. As the water is made more basic, the calcium ions react with phosphate ions to produce hydroxylapatite, Ca5(PO4)3(OH), which then precipitates out of the solution:.

Before going into hibernation bears eat constantly for what reason?

Decrease body protein

Decrease body fat

Increase body protein

increase body fat

null

What two elements make up about 99 percent of the air?

phosphorus and oxygen

nitrogen and phosphorus

helium and boron

nitrogen and oxygen

Nitrogen and oxygen make up about 99 percent of the air. Argon and carbon dioxide make up much of the rest. The air also contains water vapor. The amount of water vapor varies from place to place.

The different types of nuclei are referred to as what?

rhizomes

organelles

atoms

nuclides

Although the hydrogen nucleus consists of a single proton, the nuclei of all other elements contain both neutrons and protons. The different types of nuclei are referred to as nuclides . The number of protons in a nucleus is called the atomic number and is designated by the symbol . The total number of nucleons, neutrons and protons, is designated by the symbol and is called the mass number . A nuclide with 7 protons and 8 neutrons thus has and . The number of neutrons, , is . To specify a given nuclide, we need give only and . These can be shown in a complete nuclear symbol which takes the form.

What measure is the total mass of organisms at a trophic level?

phosphorus

detritus

atomic mass

biomass

Biomass is the total mass of organisms at a trophic level. With less energy at higher trophic levels, there are usually fewer organisms as well. This is also represented in the pyramid in Figure above . Organisms tend to be larger in size at higher trophic levels. However, their smaller numbers result in less biomass.

What has the least amount of energy in an atom?

rings

crystals

protons

electrons

The model in the Figure below shows the first four energy levels of an atom. Electrons in energy level I (also called energy level K) have the least amount of energy. As you go farther from the nucleus, electrons at higher levels have more energy, and their energy increases by a fixed, discrete amount. Electrons can jump from a lower to the next higher energy level if they absorb this amount of energy. Conversely, if electrons jump from a higher to a lower energy level, they give off energy, often in the form of light. This explains the fireworks pictured above. When the fireworks explode, electrons gain energy and jump to higher energy levels. When they jump back to their original energy levels, they release the energy as light. Different atoms have different arrangements of electrons, so they give off light of different colors. You can see an animation of electrons jumping from one energy level to another at this URL: http://cas. sdss. org/dr6/en/proj/advanced/spectraltypes/energylevels. asp .

What is the visible surface of the sun called?

ionosphere

chronosphere

stratosphere

photosphere

The photosphere is the visible surface of the Sun ( Figure below ). It's the part that we see shining. Surprisingly, the photosphere is also one of the coolest layers of the Sun. It is only about 6,000°C.

What do you call organisms that store chemical energy in carbohydrate food molecules they produce themselves?

heterotrophs

plants

omnivores

autotrophs

Autotrophs, shown in the Figure below , store chemical energy in carbohydrate food molecules they produce themselves. Food is chemical energy stored in organic molecules. Food provides both the energy to do work and the carbon to build the organic structures from cells to organisms. Because most autotrophs transform sunlight to make or synthesize food, we call the process they use photosynthesis . The food produced via this process is glucose. Only three groups of organisms - plants, algae, and some bacteria - are capable of this life-giving energy transformation. Autotrophs make food for their own use, but they make enough to support other life as well. Almost all other organisms depend absolutely on these three groups for the food they produce. The producers , as autotrophs are also known, begin food chains which feed all life. Food chains will be discussed in the Ecology concepts.

Which condition is the only autosomal trisomy where an affected individual may survive to adulthood?

type 1 diabetes

dwarfism

progeria

down syndrome

One of the most common chromosome abnormalities is Down syndrome , due to nondisjunction of chromosome 21 resulting in an extra complete chromosome 21, or part of chromosome 21 ( Figure below ). Down syndrome is the only autosomal trisomy where an affected individual may survive to adulthood. Individuals with Down syndrome often have some degree of mental retardation, some impairment of physical growth, and a specific facial appearance. With proper assistance, individuals with Down syndrome can become successful, contributing members of society. The incidence of Down syndrome increases with maternal age. The risk of having a child with Down syndrome is significantly higher among women age 35 and older.

What occurs when a population reaches the carrying capacity?

core stops

impact stops

growth increases

growth stops

A population can’t keep growing bigger and bigger forever. Sooner or later, it will run out of things it needs. For a given species, there is a maximum population that can be supported by the environment. This maximum is called the carrying capacity . When a population gets close to the carrying capacity, it usually grows more slowly. You can see this in Figure below . When the population reaches the carrying capacity, it stops growing.

What is the form of logical thinking that uses related observations to arrive at a general conclusion called?

deductive logic

hypthetical thinking

theory reasoning

inductive reasoning

There is no complete agreement when it comes to defining what the natural sciences include. For some experts, the natural sciences are astronomy, biology, chemistry, earth science, and physics. Other scholars choose to divide natural sciences into life sciences, which study living things and include biology, and physical sciences, which study nonliving matter and include astronomy, physics, and chemistry. Some disciplines such as biophysics and biochemistry build on two sciences and are interdisciplinary. Scientific Inquiry One thing is common to all forms of science: an ultimate goal “to know. ” Curiosity and inquiry are the driving forces for the development of science. Scientists seek to understand the world and the way it operates. Two methods of logical thinking are used: inductive reasoning and deductive reasoning. Inductive reasoning is a form of logical thinking that uses related observations to arrive at a general conclusion. This type of reasoning is common in descriptive science. A life scientist such as a biologist makes observations and records them.

Carbon can form single, double, or triple what with other carbon atoms

electron bonds

ionic bonds

phenotype bonds

covalent bonds

Carbon can form single, double, or triple covalent bonds with other carbon atoms.

Wind or water that travels toward the poles from the equator curves in which direction?

upward

west

downward

east

As wind or an ocean current moves, the Earth spins underneath it. Wind or water that travels toward the poles from the Equator curves to the east. Wind or water that travels toward the Equator from the poles curves to the west. The Coriolis effect bends the direction of surface currents to the right in the Northern Hemisphere. The currents curve left in the Southern Hemisphere ( Figure below ).

What is defined as the ability to cause changes in matter?

transcription

pressure

fuel

energy

The human ear is pictured below ( Figure below ). As you read about it, trace the path of sound waves through the ear. Assume a car horn blows in the distance. Sound waves spread through the air from the horn. Some of the sound waves reach your ear. The steps below show what happens next. They explain how your ears sense the sound.

Some spindle microtubules attach to the kinetochores of chromosomes and move the chromosomes to what plate?

prophase plate

boundary plate

interstitium plate

metaphase plate

null

What do plants use to make food for themselves and most other organisms?

gravity

heat

electricity

light

Visible light includes all the wavelengths of light that the human eye can detect. Humans and virtually all other organisms depend on visible light to survive. Humans and many other animals use it to see. Plants use it to make food for themselves and most other organisms.

Chlorophylls and carotenoids are the two major classes of pigments associated with what process and found in plants and algae?

glycolysis

mitosis

osmosis

photosynthesis

Understanding Pigments Different kinds of pigments exist, and each has evolved to absorb only certain wavelengths (colors) of visible light. Pigments reflect or transmit the wavelengths they cannot absorb, making them appear in the corresponding color. Chlorophylls and carotenoids are the two major classes of photosynthetic pigments found in plants and algae; each class has multiple types of pigment molecules. There are five major chlorophylls: a, b, c and d and a related molecule found in prokaryotes called bacteriochlorophyll. Chlorophyll a and chlorophyll b are found in higher plant chloroplasts and will be the focus of the following discussion. With dozens of different forms, carotenoids are a much larger group of pigments. The carotenoids found in fruit—such as the red of tomato (lycopene), the yellow of corn seeds (zeaxanthin), or the orange of an orange peel (β-carotene)—are used as advertisements to attract seed dispersers. In photosynthesis, carotenoids function as photosynthetic pigments that are very efficient molecules for the disposal of excess energy. When a leaf is exposed to full sun, the light-dependent reactions are required to process an enormous amount of energy; if that energy is not handled properly, it can do significant damage. Therefore, many carotenoids reside in the thylakoid membrane, absorb excess energy, and safely dissipate that energy as heat. Each type of pigment can be identified by the specific pattern of wavelengths it absorbs from visible light, which is the absorption spectrum. The graph in Figure 8.13 shows the absorption spectra for chlorophyll a, chlorophyll b, and a type of carotenoid pigment called β-carotene (which absorbs blue and green light). Notice how each pigment has a distinct set of peaks and troughs, revealing a highly specific pattern of absorption. Chlorophyll a absorbs wavelengths from either end of the visible spectrum (blue and red), but not green. Because green is reflected or transmitted, chlorophyll appears green. Carotenoids absorb in the short-wavelength blue region, and reflect the longer yellow, red, and orange wavelengths.

What is created when you combine simple machines?

digital devices

motors

factories

compound machines

Compound machines such as a wheelbarrow or corkscrew consist of just two simple machines. Big compound machines such as cars consist of hundreds or thousands of simple machines.

What is the general term for a parasite that causes disease ?

avian parasite

predator parasite

noxious parasite

pathogenic parasite

Bacteria: Friend or Foe? at http://biology. about. com/cs/bacteriology/a/aa032504a. htm .

What device measures atmospheric pressure and can be used as an altimeter?

indicator

thermometer

speedometer

barometer

A barometer is a device that measures atmospheric pressure. A mercury barometer is shown in Figure 11.18. This device measures atmospheric pressure, rather than gauge pressure, because there is a nearly pure vacuum above the mercury in the tube. The height of the mercury is such that hρg = P atm . When atmospheric pressure varies, the mercury rises or falls, giving important clues to weather forecasters. The barometer can also be used as an altimeter, since average atmospheric pressure varies with altitude. Mercury barometers and manometers are so common that units of mm Hg are often quoted for atmospheric pressure and blood pressures. Table 11.2 gives conversion factors for some of the more commonly used units of pressure.

What are solid-solid solutions like brass and bronze called?

amalgams

oxides

mixtures

alloys

Solid-solid solutions such as brass, bronze, and sterling silver are called alloys. Bronze (composed mainly of copper with added tin) was widely used in making weapons in times past dating back to at least 2400 B. C. This metal alloy was hard and tough, but was eventually replaced by iron.

What is the main element in organic compounds?

hydrogen

oxygen

helium

carbon

A compound found mainly in living things is known as an organic compound . Organic compounds make up the cells and other structures of organisms and carry out life processes. Carbon is the main element in organic compounds, so carbon is essential to life on Earth. Without carbon, life as we know it could not exist.

In living systems, diffusion of substances into and out of cells is mediated by the what?

battery membrane

cells membrane

Plant membrane

plasma membrane

3.5 Passive Transport The passive forms of transport, diffusion and osmosis, move material of small molecular weight. Substances diffuse from areas of high concentration to areas of low concentration, and this process continues until the substance is evenly distributed in a system. In solutions of more than one substance, each type of molecule diffuses according to its own concentration gradient. Many factors can affect the rate of diffusion, including concentration gradient, the sizes of the particles that are diffusing, and the temperature of the system. In living systems, diffusion of substances into and out of cells is mediated by the plasma membrane. Some materials diffuse readily through the membrane, but others are hindered, and their passage is only made possible by protein channels and carriers. The chemistry of living things occurs in aqueous solutions, and balancing the concentrations of those solutions is an ongoing problem. In living systems, diffusion of some substances would be slow or difficult without membrane proteins.

Desertification can result from slash-and-burn agriculture, which causes loss of what?

sediment

fertilizer

subsoil

topsoil

Slash-and-burn agriculture can lead to desertification, meaning the fertile top soil is lost.

What are certain numbers of nucleons, known as magic numbers stable against?

half-lifes

water

radiation

nuclear decay

certain numbers of nucleons, known as magic numbers, are stable against nuclear decay. These numbers of protons or neutrons (2, 8, 20, 28, 50, 82, and 126) make complete shells in the nucleus. These are similar in concept to the stable electron shells observed for the noble gases. Nuclei that have magic numbers of both protons and neutrons, such as 42 He, 168 O, 40 and 208 are called “double magic” and are particularly stable. These trends in 20 Ca, 82 Pb, nuclear stability may be rationalized by considering a quantum mechanical model of nuclear energy states analogous to that used to describe electronic states earlier in this textbook. The details of this model are beyond the scope of this chapter. Stable Nuclear Isotopes Number of Stable Isotopes.

Electron capture occurs when an inner shell electron combines with a proton and is converted into what?

protein

nuclei

photon

neutron

Figure 12.4 An overhead view of a car passing a truck on a highway. Air passing between the vehicles flows in a narrower channel and must increase its speed ( v 2 is greater than v 1 ), causing the pressure between them to drop ( P i is less than P o ). Greater pressure on the outside pushes the car and truck together.

What system consists of neurons that carry signals to skeletal muscles?

circulatory system

nervous system

endocrine system

motor system

null

Cross-pollination—or out-crossing—leads to greater genetic diversity because the microgametophyte and megagametophyte are derived from what?

dead plants

the same species

the same plant

different plants

Explore this interactive website (http://openstaxcollege. org/l/pollination) to review self-pollination and crosspollination. Living species are designed to ensure survival of their progeny; those that fail become extinct. Genetic diversity is therefore required so that in changing environmental or stress conditions, some of the progeny can survive. Self-pollination leads to the production of plants with less genetic diversity, since genetic material from the same plant is used to form gametes, and eventually, the zygote. In contrast, cross-pollination—or out-crossing—leads to greater genetic diversity because the microgametophyte and megagametophyte are derived from different plants. Because cross-pollination allows for more genetic diversity, plants have developed many ways to avoid self-pollination. In some species, the pollen and the ovary mature at different times. These flowers make self-pollination nearly impossible. By the time pollen matures and has been shed, the stigma of this flower is mature and can only be pollinated by pollen from another flower. Some flowers have developed physical features that prevent self-pollination. The primrose is one such flower. Primroses have evolved two flower types with differences in anther and stigma length: the pin-eyed flower has anthers positioned at the pollen tube’s halfway point, and the thrum-eyed flower’s stigma is likewise located at the halfway point. Insects easily cross-pollinate while seeking the nectar at the bottom of the pollen tube. This phenomenon is also known as heterostyly. Many plants, such as cucumber, have male and female flowers located on different parts of the plant, thus making self-pollination difficult. In yet other species, the male and female flowers are borne on different plants (dioecious). All of these are barriers to self-pollination; therefore, the plants depend on pollinators to transfer pollen. The majority of pollinators are biotic agents such as insects (like bees, flies, and butterflies), bats, birds, and other animals. Other plant species are pollinated by abiotic agents, such as wind and water.

Cancers are caused by a series of what?

microbes

adaptations

parasites

mutations

Cancers are caused by a series of mutations. Each mutation alters the behavior of the cell. In this example, the first mutation inactivates a tumor suppressor gene, the second mutation inactivates a DNA repair gene, the third mutation creates an oncogene, and a fourth mutation inactivates several more tumor suppressor genes, resulting in cancer. It should be noted that it does not necessarily require four or more mutations to lead to cancer.

In comparison to light, the speed of sound is faster or slower?

sound does does not travel

faster

the same

slower

Figure 17.8 When a firework explodes, the light energy is perceived before the sound energy. Sound travels more slowly than light does. (credit: Dominic Alves, Flickr).