NilsML/retriever_dataset · Datasets at Hugging Face

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Which scientist developed the theory of evolution and detailed it in the book origin of species?	Carl Sagan	Isaac Newton	Gregor Mendel	charles darwin	In his book On the Origin of Species, Darwin included a lot of evidence to show that evolution had taken place. He also made logical arguments to support his theory that evolution occurs by natural selection. Since Darwin’s time, much more evidence has been gathered. The evidence includes a huge number of fossils. It also includes more detailed knowledge of living things, right down to their DNA.
Insects are the only invertebrates that can do what?	shed	reproduce	vocalize	fly	The main reason that insects have been so successful is their ability to fly. Insects are the only invertebrates that can fly. They were also the first animals to evolve flight. The ability to fly is highly adaptive. It’s a guaranteed means of escape from nonflying predators. It’s also useful for finding food and mates.
What basic structures, found in animals and plants, are organized into tissues, organs, and organ systems?	seeds	bones	proteins	cells	null
What do we call the phase of nuclear division, in which one nucleus divides and becomes two nuclei?	cytokinesis	metaphase	prometaphase	mitosis	Mitosis is the phase of nuclear division, in which one nucleus divides and becomes two nuclei. Mitosis itself is a multi-phase process and will be the focus of the Cell Cycle: Mitosis (Advanced) concept. Immediately following mitosis is cytokinesis, in which the cytoplasm divides in half, producing two daughter cells, each containing a complete set of genetic material.
In abalones and limpets, what is conical, but somewhat flattened?	the bone	the heart	the head	the shell	null
What are the physical properties of water and carbon dioxide affected by?	temperature	weather	weight	their polarities	The physical properties of water and carbon dioxide are affected by their polarities.
Which one of newton's laws describes the direct relationship between force and acceleration?	fourth law	first law	third law	second law	Newton’s second law shows that there is a direct relationship between force and acceleration. The greater the force that is applied to an object of a given mass, the more the object will accelerate. For example, doubling the force on the object doubles its acceleration.
The process by which creatures regulate body temperature from the outside through behavioral changes is known as what?	misiothermy	endothermy	exterior induction	ectothermy	Until mammals and birds evolved, all vertebrates were ectothermic. Ectothermy means regulating body temperature from the outside through behavioral changes. For example, an ectotherm might stay under a rock in the shade in order to keep cool on a hot, sunny day. Almost all living fish, amphibians, and reptiles are ectothermic. Their metabolic rate and level of activity depend mainly on the outside temperature. They can raise or lower their own temperature only slightly through behavior alone.
Because of moving charged particles in its outer core, earth is what?	transmitter	laser	antenna	magnet	In this chapter, you learned that Earth is a magnet because of moving charged particles in its outer core. In the chapter "Electricity," you learned that moving charged particles create electric current. The next chapter explains how electric current and magnetism are related.
Color, taste, and melting point are examples of what kind of properties?	extensive properties	experimental properties	sensory properties	intensive properties	Intensive properties do not depend on the amount of the substance present. Some examples of intensive properties are color, taste, and melting point.
Amorphous selenium is a photosensitive what?	diffusion	electromagnet	insulator	semiconductor	Because amorphous selenium is a photosensitive semiconductor, exposing an electrostatically charged Se film to light causes the positive charge on the film to be discharged in all areas that are white in the original. Dark areas in the original block the light and generate an invisible, positively charged image. To produce an image on paper, negatively charged toner particles are attracted to the positive image, transferred to a negatively charged sheet of blank paper, and fused with the paper at high temperature to give a permanent image. The heaviest chalcogen, polonium, was isolated after an extraordinary effort by Marie Curie. (For more information on radioactivity and polonium, see Chapter 1 "Introduction to Chemistry", Section 1.5 "The Atom". ) Although she was never able to obtain macroscopic quantities of the element, which she named for her native country of Poland, she demonstrated that its chemistry required it to be assigned to group 16. Marie Curie was awarded a second Nobel Prize in Chemistry in 1911 for the discovery of radium and polonium.
When the rate of condensation becomes equal to the rate of vaporization, the vapor in the container is then said to be in what with the liquid?	balance	stability	synchronization	equilibrium	Vaporization and Condensation When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor in the container changes. The vapor in the container is then said to be in equilibrium with the liquid. Keep in mind that this is not a static situation, as molecules are continually exchanged between the condensed and gaseous phases. Such is an example of a dynamic equilibrium, the status of a system in.
What are the sources of sexual spores in a basidiocarp?	conidia	stamens	annulus	basidia	null
Amylose and amylopectin are the two most common components of naturally occurring what?	chromosomes	protein	carbon	starch	Amylose and amylopectin are the two most common components of naturally occurring starch. Both consist of many glucose monomers connected into a polymer. Starch serves as energy storage in plants.
Reactive, high polarized substances made of carbon bonded to one carbon atom and one hydrogen atom are known as what?	hydrocarbons	proteins	peptides	aldehydes	Aldehydes are commonly composed of a carbon bonded to one carbon atom and one hydrogen atom. Aldehydes are particularly reactive due to their high polarity, and are commonly associated with strong smells and tastes.
Relative humidity is related to the partial pressure of what in the air?	gas vapor	solid vapor	air vapor	water vapor	Relative humidity is related to the partial pressure of water vapor in the air. At 100% humidity, the partial pressure is equal to the vapor pressure, and no more water can enter the vapor phase. If the partial pressure is less than the vapor pressure, then evaporation will take place, as humidity is less than 100%. If the partial pressure is greater than the vapor pressure, condensation takes place. In everyday language, people sometimes refer to the capacity of air to “hold” water vapor, but this is not actually what happens. The water vapor is not held by the air. The amount of water in air is determined by the vapor pressure of water and has nothing to do with the properties of air.
What are the two stages in the life cycle of a jellyfish?	archangel and polyp	witch and polyp	banshee and polyp	medusa and polyp	Figure 28.10 The lifecycle of a jellyfish includes two stages: the medusa stage and the polyp stage. The polyp reproduces asexually by budding, and the medusa reproduces sexually. (credit "medusa": modification of work by Francesco Crippa).
What part of the cell holds cell organelles in place within the cytoplasm?	call wall	exoskeleton	nucleus	cytoskeleton	Crisscrossing the cytoplasm is a structure called the cytoskeleton . It consists of thread-like filaments and tubules. The cytoskeleton is like a cellular “skeleton. ” It helps the cell keep its shape. It also holds cell organelles in place within the cytoplasm.
What is the name for the process of insects transforming from a young insect to an adult?	maturation	spontaneous mutation	parthenogenesis	metamorphosis	An insect can have one of three types of metamorphosis and life cycles ( Table below ). Metamorphosis describes how insects transform from an immature or young insect into an adult insect in at least two stages. Insects may undergo gradual metamorphosis (incomplete), where transformation is subtle, or complete metamorphosis, where each stage of the life cycle appears quite different from the others. In some insects, there may be no true metamorphosis at all.
Over time, heavy metals build up in the tissues of organisms by what process?	biosynthesis	solidification	oxygenation	bioaccumulation	Heavy metals, such as mercury and lead, are toxic to living things. They can enter food chains from the atmosphere. The metals build up in the tissues of organisms by bioaccumulation . Bioaccumulation is illustrated in Figure below . As heavy metals are passed up a food chain they accumulate. Imagine a low-level consumer eating a producer. That consumer takes in all of the heavy metals from all of the producers that it eats. Then a higher-level consumer eats it and accumulates all the heavy metals from all of the lower-level consumers that it eats. In this way, heavy metals may accumulate. At high levels in the food chain, the heavy metals may be quite become quite concentrated.
Changes to what that delete, disrupt, or rearrange many loci at once are usually harmful?	cells	ribosomes	neutrons	chromosomes	null
The ability of a material to emit various wavelengths of light is similarly related to its?	molar mass	specific gravity	half-life	atomic energy levels	Fluorescence and Phosphorescence The ability of a material to emit various wavelengths of light is similarly related to its atomic energy levels. Figure 30.31 shows a scorpion illuminated by a UV lamp, sometimes called a black light. Some rocks also glow in black light, the particular colors being a function of the rock’s mineral composition. Black lights are also used to make certain posters glow.
Divergent plate boundaries rift what landforms apart, leading to the formation of a new ocean between them?	coasts	mountains	islands	continents	Divergent plate boundaries rift a continent apart. Eventually a new ocean will form between the two continents.
What mineral is stored and is maintained at normal levels in blood by the skeletal system?	magnesium	potassium	selenium	calcium	The skeletal system stores calcium and helps maintain normal levels of calcium in the blood. Bones take up and store calcium when blood levels of calcium are high. They release some of the stored calcium when blood levels of calcium are low.
What type of diseases are diseases that are caused by choices that people make in their daily lives?	contagious diseases	congenital diseases	benign diseases	lifestyle diseases	We know that many respiratory illnesses are caused by bacteria or viruses. There are steps you can take to help the spread of these pathogens, and also to prevent you from catching one. Furthermore, many respiratory illnesses are caused by poor habits, such as smoking. Many of the diseases related to smoking are called lifestyle diseases . Lifestyle diseases are diseases that are caused by choices that people make in their daily lives. For example, the choice to smoke can lead to emphysema, cancer and heart disease in later life. But you can make healthy choices instead. There are many things you can do to keep yourself healthy.
A barometer is a device that measures this?	water pressure	humidity	temperature	air pressure	Weather instruments measure weather conditions. One of the most important conditions is air pressure, which is measured with a barometer . Figure below shows how a barometer works. There are also a number of other commonly used weather instruments (see Figure below ):.
What is the term for getting the same results when an experiment is repeated, which implies the results are valid?	verification	evolution	extraction	replication	In its solid form, water is frequently referred to as ice. The terms snow, sleet, hail, or frost may also be used, depending on the conditions under which the water solidified. Ice can exist as an amorphous solid or as a crystalline solid.
Helices, spheres, and rods are examples of what distinguishing property of prokaryotic cells?	texture	color	size	shape	Most prokaryotic cells are much smaller than eukaryotic cells. Although they are tiny, prokaryotic cells can be distinguished by their shapes. The most common shapes are helices, spheres, and rods (see Figure below ).
What is the term for the change in momentum vector?	gravity	variation	release	impulse	Impulse is the change in momentum vector. Therefore the.
Larger molecules can have many, many of what that serve to keep the molecule together?	connections	arms	tubes	bonds	Larger molecules can have many, many bonds that serve to keep the molecule together. In a large sample of a given molecular compound, all of the individual molecules are identical.
What makes nobel gases unreactive?	fusion	chemical reaction	magnetism	its electon configuration	The noble gases are unreactive because of their electron configurations. American chemist Gilbert Lewis (1875-1946) used this observation to explain the types of ions and molecules that are formed by other elements. He called his explanation the octet rule. The octet rule states that elements tend to form compounds in ways that give each atom eight valence electrons. An exception to this rule is the elements in the first period, which are particularly stable when they have two valence electrons. A broader statement that encompasses both the octet rule and this exception is that atoms react in order to achieve the same valence electron configuration as that of the nearest noble gas. Most noble gases have eight valence electrons, but because the first principal energy level can hold a maximum of two electrons, the first noble gas (helium) needs only two valence electrons to fill its outermost energy level. As a result, the nearby elements hydrogen, lithium, and beryllium tend to form stable compounds by achieving a total of two valence electrons.
Which joint allows humans to sit, stand, and pivot?	femur	ankle	hip	knee	Figure 9.38 The knee joint works like a hinge to bend and straighten the lower leg. It permits a person to sit, stand, and pivot.
What type of power is generated by splitting uranium atoms?	fossil fuel power	wind power	solar power	nuclear power	Nuclear power plants use uranium that has been concentrated in fuel rods ( Figure below ). The uranium atoms are split apart when they are hit by other extremely tiny particles. These particles must be controlled or they would cause a dangerous explosion.
At any given temperature, not all of the particles of a sample of matter have the same energy of what type?	seismic	dark matter	magnetic	kinetic	At any given temperature, not all of the particles of a sample of matter have the same kinetic energy. Instead, the particles display a wide range of kinetic energies. Most of the particles have a kinetic energy near the middle of the range. However, a small number of particles have kinetic energies a great deal lower or a great deal higher than the average (see Figure below ).
Individual particles of a substance in what state are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles?	structured	stable	undivided	solid	Solids In the solid state, the individual particles of a substance are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles. As a result, solids have a definite shape and volume. Most solids are hard, but some (like waxes) are relatively soft. Many solids composed of ions can also be quite brittle. Solids usually have their constituent particles arranged in a regular, three-dimensional array of alternating positive and negative ions called a crystal. The effect of this regular arrangement of particles is sometimes visible macroscopically, as shown in Figure 8.7 "Crystalline Arrangement". Some solids, especially those composed of large molecules, cannot easily organize their particles in such regular crystals and exist as amorphous (literally, “without form”) solids. Glass is one example of an amorphous solid.
What kind of feeders are sponges?	primary feeders	bottom feeders	surface feeders	filter feeders	Sponges are filter feeders. They pump water into their body through their pores. The water flows through a large central cavity called the spongocoel (see Figure above ). As the water flows by, specialized collar cells (which are also known as choanocytes) filter out food particles such as bacteria. Collar cells have tiny hairs that trap the particles. They also have a flagellum that whips the water and keeps it moving. Once the food is trapped, the collar cells digest it (see Figure below ). Cells called amebocytes also help digest the food. They distribute the nutrients to the rest of the body as well. Finally, the water flows back out of the body through an opening called the osculum . As water flows through the sponge, oxygen diffuses from the water to the sponge’s cells. The cells also expel wastes into the water for removal through the osculum.
It is the variety of what that gives rise to the incredible variation of protein structure and function?	spastic acid side chains	clump acid side chains	organism acid side chains	amino acid side chains	Figure 15.2 Structures of the 20 amino acids found in proteins are shown. Each amino acid is composed of an amino group ( NH+ 3 ), a carboxyl group (COO ), and a side chain (blue). The side chain may be nonpolar, polar, or charged, as well as large or small. It is the variety of amino acid side chains that gives rise to the incredible variation of protein structure and function.
What do plant viruses have that protect their cells?	nuclei wall	proteins wall	inner wall	cell wall	Plant Viruses Plant viruses, like other viruses, contain a core of either DNA or RNA. You have already learned about one of these, the tobacco mosaic virus. As plant viruses have a cell wall to protect their cells, these viruses do not use receptor-mediated endocytosis to enter host cells as is seen with animal viruses. For many plant viruses to be transferred from plant to plant, damage to some of the plants’ cells must occur to allow the virus to enter a new host. This damage is often caused by weather, insects, animals, fire, or human activities like farming or landscaping. Additionally, plant offspring may inherit viral diseases from parent plants. Plant viruses can be transmitted by a variety of vectors, through contact with an infected plant’s sap, by living organisms such as insects and nematodes, and through pollen. When plants viruses are transferred between different plants, this is known as horizontal transmission, and when they are inherited from a parent, this is called vertical transmission. Symptoms of viral diseases vary according to the virus and its host (Table 21.4). One common symptom is hyperplasia, the abnormal proliferation of cells that causes the appearance of plant tumors known as galls. Other viruses induce hypoplasia, or decreased cell growth, in the leaves of plants, causing thin, yellow areas to appear. Still other viruses affect the plant by directly killing plant cells, a process known as cell necrosis. Other symptoms of plant viruses include malformed leaves, black streaks on the stems of the plants, altered growth of stems, leaves, or fruits, and ring spots, which are circular or linear areas of discoloration found in a leaf.
What type of isotope can be used to treat diseases like cancer?	radiodecaying isotope	negative isotope	positive isotope	radioactive isotopes	Radioactive isotopes are also used in the treatment of certain diseases, such as cancer. These isotopes are administered to only the diseased tissue, with the goal of destroying the unhealthy cells.
What helps by releasing chemicals that control other lymphocytes?	discharger t cells	controller t cells	interloper t cells	helper t cells	Helper T cells do not destroy infected, damaged, or cancerous body cells. However, they are still needed for an immune response. They help by releasing chemicals that control other lymphocytes. The chemicals released by helper T cells “switch on” B cells and killer T cells so they can recognize and fight specific pathogens.
What is the density needed to just halt universal expansion called?	stop density	allow density	instance density	critical density	critical density, the density needed to just halt universal expansion.
In a nuclear power plant, what typically spins in order to produce electricity?	generator	grid	pipe	turbine	Nuclear power plants use the energy they produce to heat water. The water turns into steam, which causes a turbine to spin. This, in turn, produces electricity.
How do roots and stems grow?	logically	orderly	evenly	indeterminately	null
What are organic molecules that consist of carbon, hydrogen, and oxygen called?	proteins	electrolytes	amino acids	carbohydrates	Carbohydrates are organic molecules that consist of carbon, hydrogen, and oxygen. They are made up of repeating units called saccharides. They provide cells with energy, store energy, and form structural tissues.
The diploid sporophyte produces haploid spores by what process?	electrolysis	mitosis	binary fission	meiosis	The diploid sporophyte produces haploid spores by meiosis.
What type of covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms?	acidic	ionic	polar	nonpolar	A bond in which the electronegativity difference is less than 1.7 is considered to be mostly covalent in character. However, at this point we need to distinguish between two general types of covalent bonds. A nonpolar covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms. In a nonpolar covalent bond, the distribution of electrical charge is balanced between the two atoms.
What forms a barrier between the cytoplasm and the environment outside the cell?	the cellular membrane	the splatter membrane	the mitochondria membrane	the plasma membrane	The plasma membrane forms a barrier between the cytoplasm and the environment outside the cell.
Sponges are part of what phylum, which gets its name from the latin for "having pores"?	annelida	mammalia	chordata	porifera	Sponges ( Figure below ) are classified in the phylum Porifera, from the Latin words meaning "having pores. " These pores allow the movement of water into the sponges’ sac-like bodies. Sponges must pump water through their bodies in order to eat. Because sponges are sessile , meaning they cannot move, they filter water to obtain their food. They are, therefore, known as filter feeders. Filter feeders must filter the water to separate out the organisms and nutrients they want to eat from those they do not.
Comets that have periods of 200 years or less are knows as what-period comets?	long	fast	old	short	Newly hatched loggerhead turtles start crossing the sand to the ocean.
The integumentary system helps regulate body temperature through its tight association with what system involved in our fight-or-flight responses?	endocrine system	circulatory system	autonomic nervous system	sympathetic nervous system	Thermoregulation The integumentary system helps regulate body temperature through its tight association with the sympathetic nervous system, the division of the nervous system involved in our fight-or-flight responses. The sympathetic nervous system is continuously monitoring body temperature and initiating appropriate motor responses. Recall that sweat glands, accessory structures to the skin, secrete water, salt, and other substances to cool the body when it becomes warm. Even when the body does not appear to be noticeably sweating, approximately 500 mL of sweat (insensible perspiration) are secreted a day. If the body becomes excessively warm due to high temperatures, vigorous activity (Figure 5.16ac), or a combination of the two, sweat glands will be stimulated by the sympathetic nervous system to produce large amounts of sweat, as much as 0.7 to 1.5 L per hour for an active person. When the sweat evaporates from the skin surface, the body is cooled as body heat is dissipated. In addition to sweating, arterioles in the dermis dilate so that excess heat carried by the blood can dissipate through the skin and into the surrounding environment (Figure 5.16b). This accounts for the skin redness that many people experience when exercising.
What in the air allows us to hear sound?	rain	wind	water	gases	Sound is a form of energy that travels in waves. Sound waves can’t travel through empty space, but they can travel through gases. Gases in the air allow us to hear most of the sounds in our world. Because of air, you can hear birds singing, horns tooting, and friends laughing. Without the atmosphere, the world would be a silent, eerie place.
What do you call the process in which a community changes through time?	spontaneous mutation	natural selection	continuous succession	ecological succession	Ecological succession is the process in which a community changes through time.
What is the maximum horizontal distance traveled by a projectile?	length	span	radius	range	• The maximum horizontal distance traveled by a projectile is called the range. The range launched at an angle.
The axon is a long extension of the cell body that transmits what to other cells?	blood impulses	calcium impulses	synthesis impulses	nerve impulses	The axon is a long extension of the cell body that transmits nerve impulses to other cells. The axon branches at the end, forming axon terminals . These are the points where the neuron communicates with other cells.
Fungi are now classified as their own kingdom. what kingdom were they previously a part of?	animals	protozoa	arthropods	plants	Today, fungi are no longer classified as plants. We now know that they have important traits that set them apart from plants. That’s why they are placed in their own kingdom. How do fungi differ from plants?.
What is the term for small streams?	canals	wetlands	rivers	tributaries	Small streams often flow into bigger streams or rivers. The small streams are called tributaries . A river and all its tributaries make up a river system.
A comparison of the human arm with a bat's wing demonstrates what principle of biology?	motion follows function	size follows function	attachment follows function	form follows function	dictates the form of that body part. As an example, compare your arm to a bat’s wing. While the bones of the two correspond, the parts serve different functions in each organism and their forms have adapted to follow that function. 30 Centrioles and flagella are alike in that they are made up of microtubules. In centrioles, two rings of nine microtubule “triplets” are arranged at right angles to one another. This arrangement does not occur in flagella. 32 They differ because plant cell walls are rigid. Plasmodesmata, which a plant cell needs for transportation and communication, are able to allow movement of really large molecules. Gap junctions are necessary in animal cells for transportation and communication.
What converters are used on motor vehicles to break down pollutants in exhaust to non-toxic compounds?	solvent converters	back converters	outer converters	catalytic converters	Catalytic converters are used on motor vehicles. They break down pollutants in exhaust to non-toxic compounds. For example, they change nitrogen oxides to harmless nitrogen and oxygen gasses.
If a substance does not release molecules into the air from its surface, it will not have what?	temperature	color	taste	smell	Tastes and Odors Both taste and odor stimuli are molecules taken in from the environment. The primary tastes detected by humans are sweet, sour, bitter, salty and umami. The first four tastes need little explanation. The identification of umami as a fundamental taste occurred fairly recently—it was identified in 1908 by Japanese scientist Kikunae Ikeda while he worked with seaweed broth, but it was not widely accepted as a taste that could be physiologically distinguished until many years later. The taste of umami, also known as savoriness, is attributable to the taste of the amino acid L-glutamate. In fact, monosodium glutamate, or MSG, is often used in cooking to enhance the savory taste of certain foods. What is the adaptive value of being able to distinguish umami? Savory substances tend to be high in protein. All odors that we perceive are molecules in the air we breathe. If a substance does not release molecules into the air from its surface, it has no smell. And if a human or other animal does not have a receptor that recognizes a specific molecule, then that molecule has no smell. Humans have about 350 olfactory receptor subtypes that work in various combinations to allow us to sense about 10,000 different odors. Compare that to mice, for example, which have about 1,300 olfactory receptor types, and therefore probably sense more odors. Both odors and tastes involve molecules that stimulate specific chemoreceptors. Although humans commonly distinguish taste as one sense and smell as another, they work together to create the perception of flavor. A person’s perception of flavor is reduced if he or she has congested nasal passages.
What is the term for when deep ocean water rises to the surface?	percolating	tsunami	tidal waves	upwelling	Upwelling occurs when deep ocean water rises to the surface. The water brings nutrients with it. These nutrients support many organisms.
What are collisions between gas particles and container walls called?	utilize collisions	tubes collisions	kinetic theory	elastic collisions	Collisions between gas particles and between particles and the container walls are elastic collisions.
Cooling a mixture of equal parts nitric oxide and nitrogen dioxide to −21 °c produces what?	carbon trioxide	nitrate trioxide	chloride trioxide	dinitrogen trioxide	Cooling a mixture of equal parts nitric oxide and nitrogen dioxide to −21 °C produces dinitrogen trioxide, a blue liquid consisting of N2O3 molecules (shown in Figure 18.35). Dinitrogen trioxide exists only in the liquid and solid states. When heated, it reverts to a mixture of NO and NO2.
What is the most important element to life?	hydrogen	nitrogen	calcium	carbon	Carbon is the most important element to life. Without this element, life as we know it would not exist. As you will see, carbon is the central element in compounds necessary for life.
Each female of a particular species can produce millions of these per year?	sperms	fetuses	seeds	eggs	null
The cephalic phase (reflex phase) of gastric secretion, which is relatively brief, takes place before food enters where?	skin	respiratory	Head	stomach	The cephalic phase (reflex phase) of gastric secretion, which is relatively brief, takes place before food enters the stomach. The smell, taste, sight, or thought of food triggers this phase. For example, when you bring a piece of sushi to your lips, impulses from receptors in your taste buds or the nose are relayed to your brain, which returns signals that increase gastric secretion to prepare your stomach for digestion. This enhanced secretion is a conditioned reflex, meaning it occurs only if you like or want a particular food. Depression and loss of appetite can suppress the cephalic reflex. The gastric phase of secretion lasts 3 to 4 hours, and is set in motion by local neural and hormonal mechanisms triggered by the entry of food into the stomach. For example, when your sushi reaches the stomach, it creates distention that activates the.
What part of the earth does a compass needle align with?	molecular field	gravitational field	geospatial field	magnetic field	You can use Earth's magnetic field to tell you where you want to go. A compass needle aligns with Earth’s magnetic field. People can navigate by finding magnetic north. If you know where north is, you can figure out how to get anywhere. A compass is great for finding your way when you're out in the field!.
Parasitic chelicerates like ticks and mites have evolved what?	tunicates apparatuses	licking apparatuses	aileron apparatuses	bloodsucking apparatuses	Most chelicerates ingest food using a preoral cavity formed by the chelicerae and pedipalps. Some chelicerates may secrete digestive enzymes to pre-digest food before ingesting it. Parasitic chelicerates like ticks and mites have evolved bloodsucking apparatuses. The nervous system in chelicerates consists of a brain and two ventral nerve cords. These animals use external fertilization as well as internal fertilization strategies for reproduction, depending upon the species and its habitat. Parental care for the young ranges from absolutely none to relatively prolonged care.
Where do two tributaries come together at?	snake	stream	axis	confluence	A tributary begins at its headwaters on one side of a divide. Two tributaries come together at a confluence.
The force exerted by the atmosphere on the earth’s surface can be measured with what instrument?	anemometer	mass spectrometer	Geiger counter	barometer	We can measure atmospheric pressure, the force exerted by the atmosphere on the earth’s surface, with a barometer (Figure 9.4). A barometer is a glass tube that is closed at one end, filled with a nonvolatile liquid such as mercury, and then inverted and immersed in a container of that liquid. The atmosphere exerts pressure on the liquid outside the tube, the column of liquid exerts pressure inside the tube, and the pressure at the liquid surface is the same inside and outside the tube. The height of the liquid in the tube is therefore proportional to the pressure exerted by the atmosphere.
What are the substances that the body needs for energy, building materials, and control of body processes?	tissues	liquids	gases	nutrients	Nutrients are substances that the body needs for energy, building materials, and control of body processes.
What term describes the energy required to increase the surface area of a liquid by a given amount?	boiling point	elastic collision	viscosity	surface tension	Summary Surface tension is the energy required to increase the surface area of a liquid by a given amount. The stronger the intermolecular interactions, the greater the surface tension. Surfactants are molecules, such as soaps and detergents, that reduce the surface tension of polar liquids like water. Capillary action is the phenomenon in which liquids rise up into a narrow tube called a capillary. It results whencohesive forces, the intermolecular forces in the liquid, are weaker thanadhesive forces, the attraction between a liquid and the surface of the capillary. The shape of the meniscus, the upper surface of a liquid in a tube, also reflects the balance between adhesive and cohesive forces. The viscosity of a liquid is its resistance to flow. Liquids that have strong intermolecular forces tend to have high viscosities.
What is the term for the process of turning sunlight's energy into food?	glycolysis	atherosclerosis	light compression	photosynthesis	Photosynthesis , the process of turning the energy of sunlight into ‘‘food,’’ is divided into two basic sets of reactions, known as the light reactions and the Calvin cycle, which uses carbon dioxide. As you study the details in other concepts, refer frequently to the chemical equation of photosynthesis: 6CO 2 + 6H 2 O + Light Energy → C 6 H 12 O 6 + 6O 2 . Photosynthesis occurs in the chloroplast, an organelle specific to plant cells.
Because water expands when it freezes, what property of water is lower when it is in a solid state than a liquid?	salinity	mass	volume	density	The melting point of water is 0°C. Below this temperature, water is a solid (ice). Unlike most chemical substances, water in a solid state has a lower density than water in a liquid state. This is because water expands when it freezes. Again, hydrogen bonding is the reason. Hydrogen bonds cause water molecules to line up less efficiently in ice than in liquid water. As a result, water molecules are spaced farther apart in ice, giving ice a lower density than liquid water. A substance with lower density floats on a substance with higher density. This explains why ice floats on liquid water, whereas many other solids sink to the bottom of liquid water.
What is released during dehydration synthesis?	photons	helium	air	water	Dehydration Synthesis Most macromolecules are made from single subunits, or building blocks, called monomers. The monomers combine with each other using covalent bonds to form larger molecules known as polymers. In doing so, monomers release water molecules as byproducts. This type of reaction is known as dehydration synthesis, which means “to put together while losing water.
What do plant cells have in addition to a cell wall and a large central vacuole?	chromosomes	DNA	gastropods	plastids	Plant cells have a cell wall, a large central vacuole, and plastids such as chloroplasts.
What is the only animal group that evolved to live on land and then back to live in the ocean?	birds	amphibians	reptiles	mammals	Mammals are also the only animal group that evolved to live on land and then back to live in the ocean. Whales, dolphins, and porpoises have all adapted from land-dwelling creatures to a life of swimming and reproducing in the water ( Figure below ). Whales have evolved into the largest mammals.
What has large crystals because the magma began to cool slowly, then erupted?	crystalline	lava	chalky	porphyry	This sarcophagus is housed at the Vatican Museum. The rock is the igneous extrusive rock porphyry. Porphyry has large crystals because the magma began to cool slowly, then erupted.
What must be regulated in order to maintain carbon dioxide levels and proper blood ph?	blood toxin levels	oxygen rate	Heart rate	breathing rate	Blood pH may become unbalanced if the rate of breathing is too fast or too slow. When breathing is too fast, blood contains too little carbon dioxide and becomes too basic. When breathing is too slow, blood contains too much carbon dioxide and becomes too acidic. Clearly, to maintain proper blood pH, the rate of breathing must be regulated.
Cells may enter a period of rest known as what?	respiration	anaphase	stationary phase	interkinesis	During telophase I, the spindle fiber disassembles and the nucleus reforms. The genetic material briefly uncoils back into chromatin. This is quickly followed by cytokinesis. Cells may enter a period of rest known as interkinesis or interphase II, or immediately enter meiosis II. No DNA replication occurs between meiosis I and meiosis II.
Headaches are associated with which body system?	cardiovascular system	respiratory system	circulatory system	nervous system	We all get headaches. Headaches are a relatively minor problem associated with the nervous system. But what about more serious issues of the nervous system? As you can probably imagine, these can be extremely serious.
What kind of volcano has a very wide base and is named because it looks like something a warrior would use?	arrow volcano	plate volcano	spear volcano	shield volcano	Shield volcanoes look like a huge ancient warrior’s shield laid down. Pictured above is Mauna Kea Volcano ( Figure above ) taken from Mauna Loa Volcano. Both volcanoes are part of the Big Island of Hawaii. A shield volcano has a very wide base. It is much flatter on the top than a composite volcano. The lava that creates shield volcanoes is relatively thin. The thin lava spreads out. This builds a large, flat volcano, layer by layer. The composition of lava at shield volcanoes is mafic. Shield volcanoes are very large. For example, the Mauna Loa Volcano has a diameter of more than 112 kilometers (70 miles). The volcano forms a significant part of the island of Hawaii. The top of nearby Mauna Kea Volcano is more than ten kilometers (6 miles) from its base on the seafloor.
Earth’s magnetic field is called the what?	thermosphere	ionosphere	stratosphere	magnetosphere	Like all magnets, Earth has a magnetic field. Earth’s magnetic field is called the magnetosphere . You can see a model of the magnetosphere in the Figure below . It is a huge region that extends outward from Earth in all directions. Earth exerts magnetic force over the entire field, but the force is strongest at the poles, where lines of force converge. For an animated model of the magnetosphere, watch this video: http://www. youtube. com/watch?v=5SXgOWYyn84 .
Global sources of inexpensive fossil fuels, particularly oil, are rapidly being what?	replenished	weakened	polluted	depleted	null
What is the volume of air inhaled and exhaled with each breath called?	aspiration volume	lung volume	respiration volume	tidal volume	null
What encloses and defines the borders of cells?	clear membranes	cells membranes	artificial membranes	plasma membranes	CHAPTER SUMMARY 5.1 Components and Structure The modern understanding of the plasma membrane is referred to as the fluid mosaic model. The plasma membrane is composed of a bilayer of phospholipids, with their hydrophobic, fatty acid tails in contact with each other. The landscape of the membrane is studded with proteins, some of which span the membrane. Some of these proteins serve to transport materials into or out of the cell. Carbohydrates are attached to some of the proteins and lipids on the outward-facing surface of the membrane, forming complexes that function to identify the cell to other cells. The fluid nature of the membrane is due to temperature, the configuration of the fatty acid tails (some kinked by double bonds), the presence of cholesterol embedded in the membrane, and the mosaic nature of the proteins and protein-carbohydrate combinations, which are not firmly fixed in place. Plasma membranes enclose and define the borders of cells, but rather than being a static bag, they are dynamic and constantly in flux.
What is the term for a homogeneous mixture of two or more substances?	compound	element	saturation	solution	When rocks or other substances dissolve in water, they form a solution. A solution is a homogeneous mixture of two or more substances. The particles of a solution are mixed evenly throughout it. The particles are too small to be seen or to settle out. An example of a solution is salt water.
What is the simplest life cycle?	meiosis	glycolysis	eukaryot	haploid	The haploid life cycle is the simplest life cycle. Organisms with this life cycle, such as many protists and some fungi and algae, spend the majority of their life cycle as a haploid cell. In fact, the zygote is the only diploid cell. The zygote immediately undergoes meiosis, producing four haploid cells, which grow into haploid multicellular organisms. These organisms produce gametes by mitosis. The gametes fuse through a process called syngamy to produce diploid zygotes which undergo meiosis, continuing the life cycle.
Like mammals, birds have kidneys with juxtamedullary nephrons that specialize in conserving what?	air	food	blood	water	null
What is the range of all possible frequencies of radiation called?	particles spectrum	Difused Spectrum	vibrations spectrum	electromagnetic spectrum	Visible light constitutes only one of many types of electromagnetic radiation emitted from the sun and other stars. Scientists differentiate the various types of radiant energy from the sun within the electromagnetic spectrum. The electromagnetic spectrum is the range of all possible frequencies of radiation (Figure 8.11). The difference between wavelengths relates to the amount of energy carried by them.
What type of growth generally occurs only when a population is living under ideal conditions, yet cannot continue for very long?	logarithmic growth	analogous growth	negative growth	exponential growth	With exponential growth, the population starts out growing slowly. As population size increases, the growth rate also increases. The larger the population becomes, the more quickly it grows. This type of growth generally occurs only when a population is living under ideal conditions. However, it can’t continue for very long.
What is another term for flagella?	arthropods	tendrils	dendrites	pseudopods	Why are algae considered plant-like? The main reason is that they contain chloroplasts and produce food through photosynthesis . However, they lack many other structures of true plants. For example, algae do not have roots, stems, or leaves. Some algae also differ from plants in being motile. They may move with pseudopods or flagella. Although not plants themselves, algae were probably the ancestors of plants.
Because arthropod appendages are jointed, they can do what?	eat	rotate	fly	bend	Because arthropod appendages are jointed, they can bend. This makes them flexible. Jointed appendages on the body are usually used as legs for walking or jumping. Jointed appendages on the head may be modified for other purposes. Head appendages often include upper and lower jaws. Jaws are used for eating and may also be used for defense. Sensory organs such as eyes and antennae are also found on the head. You can see some of these head appendages on the bee in Figure below .
What is the main way that wind causes erosion?	decomposition	absorption	filtration	abrasion	Abrasion is the main way that wind causes erosion. The next lesson explains how glaciers cause erosion.
Each hydrogen atom follows the octet rule with how many pairs of electrons?	four	six	eight	one	The oxygen atom follows the octet rule with two pairs of bonding electrons and two lone pairs. Each hydrogen atom follows the octet rule with one bonding pair of electrons.
What type of acid is an organic compound that is built of small units called nucleotides?	carbolic acid	citric acid	boundary acid	nucleic acid	A nucleic acid is an organic compound, such as DNA or RNA, that is built of small units called nucleotides . Many nucleotides bind together to form a chain called a polynucleotide . The nucleic acid DNA (deoxyribonucleic acid) consists of two polynucleotide chains. The nucleic acid RNA (ribonucleic acid) consists of just one polynucleotide chain.
At what temperatures do crystals formed by covalent molecular solids melt at?	high	hot	scorching	low	Physical Properties of Ionic and Covalent Compounds In general, ionic and covalent compounds have different physical properties. Ionic compounds usually form hard crystalline solids that melt at rather high temperatures and are very resistant to evaporation. These properties stem from the characteristic internal structure of an ionic solid, illustrated schematically in part (a) in Figure 2.8 "Interactions in Ionic and Covalent Solids", which shows the three-dimensional array of alternating positive and negative ions held together by strong electrostatic attractions. In contrast, as shown in part (b) in Figure 2.8 "Interactions in Ionic and Covalent Solids", most covalent compounds consist of discrete molecules held together by comparatively weak intermolecular forces (the forces between molecules), even though the atoms within each molecule are held together by strong intramolecularcovalent bonds (the forces within the molecule). Covalent substances can be gases, liquids, or solids at room temperature and pressure, depending on the strength of the intermolecular interactions. Covalent molecular solids tend to form soft crystals that melt at rather low temperatures and evaporate relatively easily.
What is the name of the rigid layer that is found outside the cell membrane and surrounds the cell?	cell envelope	cellular shield	epidermis	cell wall	A cell wall is a rigid layer that is found outside the cell membrane and surrounds the cell. The cell wall contains not only cellulose and protein, but other polysaccharides as well. The cell wall provides structural support and protection. Pores in the cell wall allow water and nutrients to move into and out of the cell. The cell wall also prevents the plant cell from bursting when water enters the cell.
Who is widely known as the father of genetics?	francis crick	walter gehring	james watson	gregor mendel	The pea plant Pisum sativum has purple and white flowers. These flowered plants are not just pretty to look at. These plants led Gregor Mendel to unlock the secrets of heredity, beginning the field of genetics. For his efforts, Mendel is widely known as the Father of Genetics, even though he knew nothing of the genetic material, DNA. The laws he developed apply to all sexually reproducing life, and are the basis for beginning to understand many human diseases.
Protozoa that cause malaria are spread by a vector, entering the blood through the bite of what insect?	wasp	fire ant	housefly	mosquito	Protozoa that cause malaria are spread by a vector. They enter the blood through the bite of an infected mosquito. They live inside red blood cells. They cause overall body pain, fever, and fatigue. Malaria kills several million people each year. Most of the deaths occur in children.
One-dimensional sinusoidal waves show the relationship among wavelength, frequency, and what?	friction	velocity	motion	speed	Figure 6.2 One-dimensional sinusoidal waves show the relationship among wavelength, frequency, and speed. The wave with the shortest wavelength has the highest frequency. Amplitude is one-half the height of the wave from peak to trough.

Which scientist developed the theory of evolution and detailed it in the book origin of species?

Carl Sagan

Isaac Newton

Gregor Mendel

charles darwin

In his book On the Origin of Species, Darwin included a lot of evidence to show that evolution had taken place. He also made logical arguments to support his theory that evolution occurs by natural selection. Since Darwin’s time, much more evidence has been gathered. The evidence includes a huge number of fossils. It also includes more detailed knowledge of living things, right down to their DNA.

Insects are the only invertebrates that can do what?

shed

reproduce

vocalize

fly

The main reason that insects have been so successful is their ability to fly. Insects are the only invertebrates that can fly. They were also the first animals to evolve flight. The ability to fly is highly adaptive. It’s a guaranteed means of escape from nonflying predators. It’s also useful for finding food and mates.

What basic structures, found in animals and plants, are organized into tissues, organs, and organ systems?

seeds

bones

proteins

cells

null

What do we call the phase of nuclear division, in which one nucleus divides and becomes two nuclei?

cytokinesis

metaphase

prometaphase

mitosis

Mitosis is the phase of nuclear division, in which one nucleus divides and becomes two nuclei. Mitosis itself is a multi-phase process and will be the focus of the Cell Cycle: Mitosis (Advanced) concept. Immediately following mitosis is cytokinesis, in which the cytoplasm divides in half, producing two daughter cells, each containing a complete set of genetic material.

In abalones and limpets, what is conical, but somewhat flattened?

the bone

the heart

the head

the shell

null

What are the physical properties of water and carbon dioxide affected by?

temperature

weather

weight

their polarities

The physical properties of water and carbon dioxide are affected by their polarities.

Which one of newton's laws describes the direct relationship between force and acceleration?

fourth law

first law

third law

second law

Newton’s second law shows that there is a direct relationship between force and acceleration. The greater the force that is applied to an object of a given mass, the more the object will accelerate. For example, doubling the force on the object doubles its acceleration.

The process by which creatures regulate body temperature from the outside through behavioral changes is known as what?

misiothermy

endothermy

exterior induction

ectothermy

Until mammals and birds evolved, all vertebrates were ectothermic. Ectothermy means regulating body temperature from the outside through behavioral changes. For example, an ectotherm might stay under a rock in the shade in order to keep cool on a hot, sunny day. Almost all living fish, amphibians, and reptiles are ectothermic. Their metabolic rate and level of activity depend mainly on the outside temperature. They can raise or lower their own temperature only slightly through behavior alone.

Because of moving charged particles in its outer core, earth is what?

transmitter

laser

antenna

magnet

In this chapter, you learned that Earth is a magnet because of moving charged particles in its outer core. In the chapter "Electricity," you learned that moving charged particles create electric current. The next chapter explains how electric current and magnetism are related.

Color, taste, and melting point are examples of what kind of properties?

extensive properties

experimental properties

sensory properties

intensive properties

Intensive properties do not depend on the amount of the substance present. Some examples of intensive properties are color, taste, and melting point.

Amorphous selenium is a photosensitive what?

diffusion

electromagnet

insulator

semiconductor

Because amorphous selenium is a photosensitive semiconductor, exposing an electrostatically charged Se film to light causes the positive charge on the film to be discharged in all areas that are white in the original. Dark areas in the original block the light and generate an invisible, positively charged image. To produce an image on paper, negatively charged toner particles are attracted to the positive image, transferred to a negatively charged sheet of blank paper, and fused with the paper at high temperature to give a permanent image. The heaviest chalcogen, polonium, was isolated after an extraordinary effort by Marie Curie. (For more information on radioactivity and polonium, see Chapter 1 "Introduction to Chemistry", Section 1.5 "The Atom". ) Although she was never able to obtain macroscopic quantities of the element, which she named for her native country of Poland, she demonstrated that its chemistry required it to be assigned to group 16. Marie Curie was awarded a second Nobel Prize in Chemistry in 1911 for the discovery of radium and polonium.

When the rate of condensation becomes equal to the rate of vaporization, the vapor in the container is then said to be in what with the liquid?

balance

stability

synchronization

equilibrium

Vaporization and Condensation When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor in the container changes. The vapor in the container is then said to be in equilibrium with the liquid. Keep in mind that this is not a static situation, as molecules are continually exchanged between the condensed and gaseous phases. Such is an example of a dynamic equilibrium, the status of a system in.

What are the sources of sexual spores in a basidiocarp?

conidia

stamens

annulus

basidia

null

Amylose and amylopectin are the two most common components of naturally occurring what?

chromosomes

protein

carbon

starch

Amylose and amylopectin are the two most common components of naturally occurring starch. Both consist of many glucose monomers connected into a polymer. Starch serves as energy storage in plants.

Reactive, high polarized substances made of carbon bonded to one carbon atom and one hydrogen atom are known as what?

hydrocarbons

proteins

peptides

aldehydes

Aldehydes are commonly composed of a carbon bonded to one carbon atom and one hydrogen atom. Aldehydes are particularly reactive due to their high polarity, and are commonly associated with strong smells and tastes.

Relative humidity is related to the partial pressure of what in the air?

gas vapor

solid vapor

air vapor

water vapor

Relative humidity is related to the partial pressure of water vapor in the air. At 100% humidity, the partial pressure is equal to the vapor pressure, and no more water can enter the vapor phase. If the partial pressure is less than the vapor pressure, then evaporation will take place, as humidity is less than 100%. If the partial pressure is greater than the vapor pressure, condensation takes place. In everyday language, people sometimes refer to the capacity of air to “hold” water vapor, but this is not actually what happens. The water vapor is not held by the air. The amount of water in air is determined by the vapor pressure of water and has nothing to do with the properties of air.

What are the two stages in the life cycle of a jellyfish?

archangel and polyp

witch and polyp

banshee and polyp

medusa and polyp

Figure 28.10 The lifecycle of a jellyfish includes two stages: the medusa stage and the polyp stage. The polyp reproduces asexually by budding, and the medusa reproduces sexually. (credit "medusa": modification of work by Francesco Crippa).

What part of the cell holds cell organelles in place within the cytoplasm?

call wall

exoskeleton

nucleus

cytoskeleton

Crisscrossing the cytoplasm is a structure called the cytoskeleton . It consists of thread-like filaments and tubules. The cytoskeleton is like a cellular “skeleton. ” It helps the cell keep its shape. It also holds cell organelles in place within the cytoplasm.

What is the name for the process of insects transforming from a young insect to an adult?

maturation

spontaneous mutation

parthenogenesis

metamorphosis

An insect can have one of three types of metamorphosis and life cycles ( Table below ). Metamorphosis describes how insects transform from an immature or young insect into an adult insect in at least two stages. Insects may undergo gradual metamorphosis (incomplete), where transformation is subtle, or complete metamorphosis, where each stage of the life cycle appears quite different from the others. In some insects, there may be no true metamorphosis at all.

Over time, heavy metals build up in the tissues of organisms by what process?

biosynthesis

solidification

oxygenation

bioaccumulation

Heavy metals, such as mercury and lead, are toxic to living things. They can enter food chains from the atmosphere. The metals build up in the tissues of organisms by bioaccumulation . Bioaccumulation is illustrated in Figure below . As heavy metals are passed up a food chain they accumulate. Imagine a low-level consumer eating a producer. That consumer takes in all of the heavy metals from all of the producers that it eats. Then a higher-level consumer eats it and accumulates all the heavy metals from all of the lower-level consumers that it eats. In this way, heavy metals may accumulate. At high levels in the food chain, the heavy metals may be quite become quite concentrated.

Changes to what that delete, disrupt, or rearrange many loci at once are usually harmful?

cells

ribosomes

neutrons

chromosomes

null

The ability of a material to emit various wavelengths of light is similarly related to its?

molar mass

specific gravity

half-life

atomic energy levels

Fluorescence and Phosphorescence The ability of a material to emit various wavelengths of light is similarly related to its atomic energy levels. Figure 30.31 shows a scorpion illuminated by a UV lamp, sometimes called a black light. Some rocks also glow in black light, the particular colors being a function of the rock’s mineral composition. Black lights are also used to make certain posters glow.

Divergent plate boundaries rift what landforms apart, leading to the formation of a new ocean between them?

coasts

mountains

islands

continents

Divergent plate boundaries rift a continent apart. Eventually a new ocean will form between the two continents.

What mineral is stored and is maintained at normal levels in blood by the skeletal system?

magnesium

potassium

selenium

calcium

The skeletal system stores calcium and helps maintain normal levels of calcium in the blood. Bones take up and store calcium when blood levels of calcium are high. They release some of the stored calcium when blood levels of calcium are low.

What type of diseases are diseases that are caused by choices that people make in their daily lives?

contagious diseases

congenital diseases

benign diseases

lifestyle diseases

We know that many respiratory illnesses are caused by bacteria or viruses. There are steps you can take to help the spread of these pathogens, and also to prevent you from catching one. Furthermore, many respiratory illnesses are caused by poor habits, such as smoking. Many of the diseases related to smoking are called lifestyle diseases . Lifestyle diseases are diseases that are caused by choices that people make in their daily lives. For example, the choice to smoke can lead to emphysema, cancer and heart disease in later life. But you can make healthy choices instead. There are many things you can do to keep yourself healthy.

A barometer is a device that measures this?

water pressure

humidity

temperature

air pressure

Weather instruments measure weather conditions. One of the most important conditions is air pressure, which is measured with a barometer . Figure below shows how a barometer works. There are also a number of other commonly used weather instruments (see Figure below ):.

What is the term for getting the same results when an experiment is repeated, which implies the results are valid?

verification

evolution

extraction

replication

In its solid form, water is frequently referred to as ice. The terms snow, sleet, hail, or frost may also be used, depending on the conditions under which the water solidified. Ice can exist as an amorphous solid or as a crystalline solid.

Helices, spheres, and rods are examples of what distinguishing property of prokaryotic cells?

texture

color

size

shape

Most prokaryotic cells are much smaller than eukaryotic cells. Although they are tiny, prokaryotic cells can be distinguished by their shapes. The most common shapes are helices, spheres, and rods (see Figure below ).

What is the term for the change in momentum vector?

gravity

variation

release

impulse

Impulse is the change in momentum vector. Therefore the.

Larger molecules can have many, many of what that serve to keep the molecule together?

connections

arms

tubes

bonds

Larger molecules can have many, many bonds that serve to keep the molecule together. In a large sample of a given molecular compound, all of the individual molecules are identical.

What makes nobel gases unreactive?

fusion

chemical reaction

magnetism

its electon configuration

The noble gases are unreactive because of their electron configurations. American chemist Gilbert Lewis (1875-1946) used this observation to explain the types of ions and molecules that are formed by other elements. He called his explanation the octet rule. The octet rule states that elements tend to form compounds in ways that give each atom eight valence electrons. An exception to this rule is the elements in the first period, which are particularly stable when they have two valence electrons. A broader statement that encompasses both the octet rule and this exception is that atoms react in order to achieve the same valence electron configuration as that of the nearest noble gas. Most noble gases have eight valence electrons, but because the first principal energy level can hold a maximum of two electrons, the first noble gas (helium) needs only two valence electrons to fill its outermost energy level. As a result, the nearby elements hydrogen, lithium, and beryllium tend to form stable compounds by achieving a total of two valence electrons.

Which joint allows humans to sit, stand, and pivot?

femur

ankle

hip

knee

Figure 9.38 The knee joint works like a hinge to bend and straighten the lower leg. It permits a person to sit, stand, and pivot.

What type of power is generated by splitting uranium atoms?

fossil fuel power

wind power

solar power

nuclear power

Nuclear power plants use uranium that has been concentrated in fuel rods ( Figure below ). The uranium atoms are split apart when they are hit by other extremely tiny particles. These particles must be controlled or they would cause a dangerous explosion.

At any given temperature, not all of the particles of a sample of matter have the same energy of what type?

seismic

dark matter

magnetic

kinetic

At any given temperature, not all of the particles of a sample of matter have the same kinetic energy. Instead, the particles display a wide range of kinetic energies. Most of the particles have a kinetic energy near the middle of the range. However, a small number of particles have kinetic energies a great deal lower or a great deal higher than the average (see Figure below ).

Individual particles of a substance in what state are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles?

structured

stable

undivided

solid

Solids In the solid state, the individual particles of a substance are in fixed positions with respect to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles. As a result, solids have a definite shape and volume. Most solids are hard, but some (like waxes) are relatively soft. Many solids composed of ions can also be quite brittle. Solids usually have their constituent particles arranged in a regular, three-dimensional array of alternating positive and negative ions called a crystal. The effect of this regular arrangement of particles is sometimes visible macroscopically, as shown in Figure 8.7 "Crystalline Arrangement". Some solids, especially those composed of large molecules, cannot easily organize their particles in such regular crystals and exist as amorphous (literally, “without form”) solids. Glass is one example of an amorphous solid.

What kind of feeders are sponges?

primary feeders

bottom feeders

surface feeders

filter feeders

Sponges are filter feeders. They pump water into their body through their pores. The water flows through a large central cavity called the spongocoel (see Figure above ). As the water flows by, specialized collar cells (which are also known as choanocytes) filter out food particles such as bacteria. Collar cells have tiny hairs that trap the particles. They also have a flagellum that whips the water and keeps it moving. Once the food is trapped, the collar cells digest it (see Figure below ). Cells called amebocytes also help digest the food. They distribute the nutrients to the rest of the body as well. Finally, the water flows back out of the body through an opening called the osculum . As water flows through the sponge, oxygen diffuses from the water to the sponge’s cells. The cells also expel wastes into the water for removal through the osculum.

It is the variety of what that gives rise to the incredible variation of protein structure and function?

spastic acid side chains

clump acid side chains

organism acid side chains

amino acid side chains

Figure 15.2 Structures of the 20 amino acids found in proteins are shown. Each amino acid is composed of an amino group ( NH+ 3 ), a carboxyl group (COO ), and a side chain (blue). The side chain may be nonpolar, polar, or charged, as well as large or small. It is the variety of amino acid side chains that gives rise to the incredible variation of protein structure and function.

What do plant viruses have that protect their cells?

nuclei wall

proteins wall

inner wall

cell wall

Plant Viruses Plant viruses, like other viruses, contain a core of either DNA or RNA. You have already learned about one of these, the tobacco mosaic virus. As plant viruses have a cell wall to protect their cells, these viruses do not use receptor-mediated endocytosis to enter host cells as is seen with animal viruses. For many plant viruses to be transferred from plant to plant, damage to some of the plants’ cells must occur to allow the virus to enter a new host. This damage is often caused by weather, insects, animals, fire, or human activities like farming or landscaping. Additionally, plant offspring may inherit viral diseases from parent plants. Plant viruses can be transmitted by a variety of vectors, through contact with an infected plant’s sap, by living organisms such as insects and nematodes, and through pollen. When plants viruses are transferred between different plants, this is known as horizontal transmission, and when they are inherited from a parent, this is called vertical transmission. Symptoms of viral diseases vary according to the virus and its host (Table 21.4). One common symptom is hyperplasia, the abnormal proliferation of cells that causes the appearance of plant tumors known as galls. Other viruses induce hypoplasia, or decreased cell growth, in the leaves of plants, causing thin, yellow areas to appear. Still other viruses affect the plant by directly killing plant cells, a process known as cell necrosis. Other symptoms of plant viruses include malformed leaves, black streaks on the stems of the plants, altered growth of stems, leaves, or fruits, and ring spots, which are circular or linear areas of discoloration found in a leaf.

What type of isotope can be used to treat diseases like cancer?

radiodecaying isotope

negative isotope

positive isotope

radioactive isotopes

Radioactive isotopes are also used in the treatment of certain diseases, such as cancer. These isotopes are administered to only the diseased tissue, with the goal of destroying the unhealthy cells.

What helps by releasing chemicals that control other lymphocytes?

discharger t cells

controller t cells

interloper t cells

helper t cells

Helper T cells do not destroy infected, damaged, or cancerous body cells. However, they are still needed for an immune response. They help by releasing chemicals that control other lymphocytes. The chemicals released by helper T cells “switch on” B cells and killer T cells so they can recognize and fight specific pathogens.

What is the density needed to just halt universal expansion called?

stop density

allow density

instance density

critical density

critical density, the density needed to just halt universal expansion.

In a nuclear power plant, what typically spins in order to produce electricity?

generator

grid

pipe

turbine

Nuclear power plants use the energy they produce to heat water. The water turns into steam, which causes a turbine to spin. This, in turn, produces electricity.

How do roots and stems grow?

logically

orderly

evenly

indeterminately

null

What are organic molecules that consist of carbon, hydrogen, and oxygen called?

proteins

electrolytes

amino acids

carbohydrates

Carbohydrates are organic molecules that consist of carbon, hydrogen, and oxygen. They are made up of repeating units called saccharides. They provide cells with energy, store energy, and form structural tissues.

The diploid sporophyte produces haploid spores by what process?

electrolysis

mitosis

binary fission

meiosis

The diploid sporophyte produces haploid spores by meiosis.

What type of covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms?

acidic

ionic

polar

nonpolar

A bond in which the electronegativity difference is less than 1.7 is considered to be mostly covalent in character. However, at this point we need to distinguish between two general types of covalent bonds. A nonpolar covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms. In a nonpolar covalent bond, the distribution of electrical charge is balanced between the two atoms.

What forms a barrier between the cytoplasm and the environment outside the cell?

the cellular membrane

the splatter membrane

the mitochondria membrane

the plasma membrane

The plasma membrane forms a barrier between the cytoplasm and the environment outside the cell.

Sponges are part of what phylum, which gets its name from the latin for "having pores"?

annelida

mammalia

chordata

porifera

Sponges ( Figure below ) are classified in the phylum Porifera, from the Latin words meaning "having pores. " These pores allow the movement of water into the sponges’ sac-like bodies. Sponges must pump water through their bodies in order to eat. Because sponges are sessile , meaning they cannot move, they filter water to obtain their food. They are, therefore, known as filter feeders. Filter feeders must filter the water to separate out the organisms and nutrients they want to eat from those they do not.

Comets that have periods of 200 years or less are knows as what-period comets?

long

fast

old

short

Newly hatched loggerhead turtles start crossing the sand to the ocean.

The integumentary system helps regulate body temperature through its tight association with what system involved in our fight-or-flight responses?

endocrine system

circulatory system

autonomic nervous system

sympathetic nervous system

Thermoregulation The integumentary system helps regulate body temperature through its tight association with the sympathetic nervous system, the division of the nervous system involved in our fight-or-flight responses. The sympathetic nervous system is continuously monitoring body temperature and initiating appropriate motor responses. Recall that sweat glands, accessory structures to the skin, secrete water, salt, and other substances to cool the body when it becomes warm. Even when the body does not appear to be noticeably sweating, approximately 500 mL of sweat (insensible perspiration) are secreted a day. If the body becomes excessively warm due to high temperatures, vigorous activity (Figure 5.16ac), or a combination of the two, sweat glands will be stimulated by the sympathetic nervous system to produce large amounts of sweat, as much as 0.7 to 1.5 L per hour for an active person. When the sweat evaporates from the skin surface, the body is cooled as body heat is dissipated. In addition to sweating, arterioles in the dermis dilate so that excess heat carried by the blood can dissipate through the skin and into the surrounding environment (Figure 5.16b). This accounts for the skin redness that many people experience when exercising.

What in the air allows us to hear sound?

rain

wind

water

gases

Sound is a form of energy that travels in waves. Sound waves can’t travel through empty space, but they can travel through gases. Gases in the air allow us to hear most of the sounds in our world. Because of air, you can hear birds singing, horns tooting, and friends laughing. Without the atmosphere, the world would be a silent, eerie place.

What do you call the process in which a community changes through time?

spontaneous mutation

natural selection

continuous succession

ecological succession

Ecological succession is the process in which a community changes through time.

What is the maximum horizontal distance traveled by a projectile?

length

span

radius

range

• The maximum horizontal distance traveled by a projectile is called the range. The range launched at an angle.

The axon is a long extension of the cell body that transmits what to other cells?

blood impulses

calcium impulses

synthesis impulses

nerve impulses

The axon is a long extension of the cell body that transmits nerve impulses to other cells. The axon branches at the end, forming axon terminals . These are the points where the neuron communicates with other cells.

Fungi are now classified as their own kingdom. what kingdom were they previously a part of?

animals

protozoa

arthropods

plants

Today, fungi are no longer classified as plants. We now know that they have important traits that set them apart from plants. That’s why they are placed in their own kingdom. How do fungi differ from plants?.

What is the term for small streams?

canals

wetlands

rivers

tributaries

Small streams often flow into bigger streams or rivers. The small streams are called tributaries . A river and all its tributaries make up a river system.

A comparison of the human arm with a bat's wing demonstrates what principle of biology?

motion follows function

size follows function

attachment follows function

form follows function

dictates the form of that body part. As an example, compare your arm to a bat’s wing. While the bones of the two correspond, the parts serve different functions in each organism and their forms have adapted to follow that function. 30 Centrioles and flagella are alike in that they are made up of microtubules. In centrioles, two rings of nine microtubule “triplets” are arranged at right angles to one another. This arrangement does not occur in flagella. 32 They differ because plant cell walls are rigid. Plasmodesmata, which a plant cell needs for transportation and communication, are able to allow movement of really large molecules. Gap junctions are necessary in animal cells for transportation and communication.

What converters are used on motor vehicles to break down pollutants in exhaust to non-toxic compounds?

solvent converters

back converters

outer converters

catalytic converters

Catalytic converters are used on motor vehicles. They break down pollutants in exhaust to non-toxic compounds. For example, they change nitrogen oxides to harmless nitrogen and oxygen gasses.

If a substance does not release molecules into the air from its surface, it will not have what?

temperature

color

taste

smell

Tastes and Odors Both taste and odor stimuli are molecules taken in from the environment. The primary tastes detected by humans are sweet, sour, bitter, salty and umami. The first four tastes need little explanation. The identification of umami as a fundamental taste occurred fairly recently—it was identified in 1908 by Japanese scientist Kikunae Ikeda while he worked with seaweed broth, but it was not widely accepted as a taste that could be physiologically distinguished until many years later. The taste of umami, also known as savoriness, is attributable to the taste of the amino acid L-glutamate. In fact, monosodium glutamate, or MSG, is often used in cooking to enhance the savory taste of certain foods. What is the adaptive value of being able to distinguish umami? Savory substances tend to be high in protein. All odors that we perceive are molecules in the air we breathe. If a substance does not release molecules into the air from its surface, it has no smell. And if a human or other animal does not have a receptor that recognizes a specific molecule, then that molecule has no smell. Humans have about 350 olfactory receptor subtypes that work in various combinations to allow us to sense about 10,000 different odors. Compare that to mice, for example, which have about 1,300 olfactory receptor types, and therefore probably sense more odors. Both odors and tastes involve molecules that stimulate specific chemoreceptors. Although humans commonly distinguish taste as one sense and smell as another, they work together to create the perception of flavor. A person’s perception of flavor is reduced if he or she has congested nasal passages.

What is the term for when deep ocean water rises to the surface?

percolating

tsunami

tidal waves

upwelling

Upwelling occurs when deep ocean water rises to the surface. The water brings nutrients with it. These nutrients support many organisms.

What are collisions between gas particles and container walls called?

utilize collisions

tubes collisions

kinetic theory

elastic collisions

Collisions between gas particles and between particles and the container walls are elastic collisions.

Cooling a mixture of equal parts nitric oxide and nitrogen dioxide to −21 °c produces what?

carbon trioxide

nitrate trioxide

chloride trioxide

dinitrogen trioxide

Cooling a mixture of equal parts nitric oxide and nitrogen dioxide to −21 °C produces dinitrogen trioxide, a blue liquid consisting of N2O3 molecules (shown in Figure 18.35). Dinitrogen trioxide exists only in the liquid and solid states. When heated, it reverts to a mixture of NO and NO2.

What is the most important element to life?

hydrogen

nitrogen

calcium

carbon

Carbon is the most important element to life. Without this element, life as we know it would not exist. As you will see, carbon is the central element in compounds necessary for life.

Each female of a particular species can produce millions of these per year?

sperms

fetuses

seeds

eggs

null

The cephalic phase (reflex phase) of gastric secretion, which is relatively brief, takes place before food enters where?

skin

respiratory

Head

stomach

The cephalic phase (reflex phase) of gastric secretion, which is relatively brief, takes place before food enters the stomach. The smell, taste, sight, or thought of food triggers this phase. For example, when you bring a piece of sushi to your lips, impulses from receptors in your taste buds or the nose are relayed to your brain, which returns signals that increase gastric secretion to prepare your stomach for digestion. This enhanced secretion is a conditioned reflex, meaning it occurs only if you like or want a particular food. Depression and loss of appetite can suppress the cephalic reflex. The gastric phase of secretion lasts 3 to 4 hours, and is set in motion by local neural and hormonal mechanisms triggered by the entry of food into the stomach. For example, when your sushi reaches the stomach, it creates distention that activates the.

What part of the earth does a compass needle align with?

molecular field

gravitational field

geospatial field

magnetic field

You can use Earth's magnetic field to tell you where you want to go. A compass needle aligns with Earth’s magnetic field. People can navigate by finding magnetic north. If you know where north is, you can figure out how to get anywhere. A compass is great for finding your way when you're out in the field!.

Parasitic chelicerates like ticks and mites have evolved what?

tunicates apparatuses

licking apparatuses

aileron apparatuses

bloodsucking apparatuses

Most chelicerates ingest food using a preoral cavity formed by the chelicerae and pedipalps. Some chelicerates may secrete digestive enzymes to pre-digest food before ingesting it. Parasitic chelicerates like ticks and mites have evolved bloodsucking apparatuses. The nervous system in chelicerates consists of a brain and two ventral nerve cords. These animals use external fertilization as well as internal fertilization strategies for reproduction, depending upon the species and its habitat. Parental care for the young ranges from absolutely none to relatively prolonged care.

Where do two tributaries come together at?

snake

stream

axis

confluence

A tributary begins at its headwaters on one side of a divide. Two tributaries come together at a confluence.

The force exerted by the atmosphere on the earth’s surface can be measured with what instrument?

anemometer

mass spectrometer

Geiger counter

barometer

We can measure atmospheric pressure, the force exerted by the atmosphere on the earth’s surface, with a barometer (Figure 9.4). A barometer is a glass tube that is closed at one end, filled with a nonvolatile liquid such as mercury, and then inverted and immersed in a container of that liquid. The atmosphere exerts pressure on the liquid outside the tube, the column of liquid exerts pressure inside the tube, and the pressure at the liquid surface is the same inside and outside the tube. The height of the liquid in the tube is therefore proportional to the pressure exerted by the atmosphere.

What are the substances that the body needs for energy, building materials, and control of body processes?

tissues

liquids

gases

nutrients

Nutrients are substances that the body needs for energy, building materials, and control of body processes.

What term describes the energy required to increase the surface area of a liquid by a given amount?

boiling point

elastic collision

viscosity

surface tension

Summary Surface tension is the energy required to increase the surface area of a liquid by a given amount. The stronger the intermolecular interactions, the greater the surface tension. Surfactants are molecules, such as soaps and detergents, that reduce the surface tension of polar liquids like water. Capillary action is the phenomenon in which liquids rise up into a narrow tube called a capillary. It results whencohesive forces, the intermolecular forces in the liquid, are weaker thanadhesive forces, the attraction between a liquid and the surface of the capillary. The shape of the meniscus, the upper surface of a liquid in a tube, also reflects the balance between adhesive and cohesive forces. The viscosity of a liquid is its resistance to flow. Liquids that have strong intermolecular forces tend to have high viscosities.

What is the term for the process of turning sunlight's energy into food?

glycolysis

atherosclerosis

light compression

photosynthesis

Photosynthesis , the process of turning the energy of sunlight into ‘‘food,’’ is divided into two basic sets of reactions, known as the light reactions and the Calvin cycle, which uses carbon dioxide. As you study the details in other concepts, refer frequently to the chemical equation of photosynthesis: 6CO 2 + 6H 2 O + Light Energy → C 6 H 12 O 6 + 6O 2 . Photosynthesis occurs in the chloroplast, an organelle specific to plant cells.

Because water expands when it freezes, what property of water is lower when it is in a solid state than a liquid?

salinity

mass

volume

density

The melting point of water is 0°C. Below this temperature, water is a solid (ice). Unlike most chemical substances, water in a solid state has a lower density than water in a liquid state. This is because water expands when it freezes. Again, hydrogen bonding is the reason. Hydrogen bonds cause water molecules to line up less efficiently in ice than in liquid water. As a result, water molecules are spaced farther apart in ice, giving ice a lower density than liquid water. A substance with lower density floats on a substance with higher density. This explains why ice floats on liquid water, whereas many other solids sink to the bottom of liquid water.

What is released during dehydration synthesis?

photons

helium

air

water

Dehydration Synthesis Most macromolecules are made from single subunits, or building blocks, called monomers. The monomers combine with each other using covalent bonds to form larger molecules known as polymers. In doing so, monomers release water molecules as byproducts. This type of reaction is known as dehydration synthesis, which means “to put together while losing water.

What do plant cells have in addition to a cell wall and a large central vacuole?

chromosomes

DNA

gastropods

plastids

Plant cells have a cell wall, a large central vacuole, and plastids such as chloroplasts.

What is the only animal group that evolved to live on land and then back to live in the ocean?

birds

amphibians

reptiles

mammals

Mammals are also the only animal group that evolved to live on land and then back to live in the ocean. Whales, dolphins, and porpoises have all adapted from land-dwelling creatures to a life of swimming and reproducing in the water ( Figure below ). Whales have evolved into the largest mammals.

What has large crystals because the magma began to cool slowly, then erupted?

crystalline

lava

chalky

porphyry

This sarcophagus is housed at the Vatican Museum. The rock is the igneous extrusive rock porphyry. Porphyry has large crystals because the magma began to cool slowly, then erupted.

What must be regulated in order to maintain carbon dioxide levels and proper blood ph?

blood toxin levels

oxygen rate

Heart rate

breathing rate

Blood pH may become unbalanced if the rate of breathing is too fast or too slow. When breathing is too fast, blood contains too little carbon dioxide and becomes too basic. When breathing is too slow, blood contains too much carbon dioxide and becomes too acidic. Clearly, to maintain proper blood pH, the rate of breathing must be regulated.

Cells may enter a period of rest known as what?

respiration

anaphase

stationary phase

interkinesis

During telophase I, the spindle fiber disassembles and the nucleus reforms. The genetic material briefly uncoils back into chromatin. This is quickly followed by cytokinesis. Cells may enter a period of rest known as interkinesis or interphase II, or immediately enter meiosis II. No DNA replication occurs between meiosis I and meiosis II.

Headaches are associated with which body system?

cardiovascular system

respiratory system

circulatory system

nervous system

We all get headaches. Headaches are a relatively minor problem associated with the nervous system. But what about more serious issues of the nervous system? As you can probably imagine, these can be extremely serious.

What kind of volcano has a very wide base and is named because it looks like something a warrior would use?

arrow volcano

plate volcano

spear volcano

shield volcano

Shield volcanoes look like a huge ancient warrior’s shield laid down. Pictured above is Mauna Kea Volcano ( Figure above ) taken from Mauna Loa Volcano. Both volcanoes are part of the Big Island of Hawaii. A shield volcano has a very wide base. It is much flatter on the top than a composite volcano. The lava that creates shield volcanoes is relatively thin. The thin lava spreads out. This builds a large, flat volcano, layer by layer. The composition of lava at shield volcanoes is mafic. Shield volcanoes are very large. For example, the Mauna Loa Volcano has a diameter of more than 112 kilometers (70 miles). The volcano forms a significant part of the island of Hawaii. The top of nearby Mauna Kea Volcano is more than ten kilometers (6 miles) from its base on the seafloor.

Earth’s magnetic field is called the what?

thermosphere

ionosphere

stratosphere

magnetosphere

Like all magnets, Earth has a magnetic field. Earth’s magnetic field is called the magnetosphere . You can see a model of the magnetosphere in the Figure below . It is a huge region that extends outward from Earth in all directions. Earth exerts magnetic force over the entire field, but the force is strongest at the poles, where lines of force converge. For an animated model of the magnetosphere, watch this video: http://www. youtube. com/watch?v=5SXgOWYyn84 .

Global sources of inexpensive fossil fuels, particularly oil, are rapidly being what?

replenished

weakened

polluted

depleted

null

What is the volume of air inhaled and exhaled with each breath called?

aspiration volume

lung volume

respiration volume

tidal volume

null

What encloses and defines the borders of cells?

clear membranes

cells membranes

artificial membranes

plasma membranes

CHAPTER SUMMARY 5.1 Components and Structure The modern understanding of the plasma membrane is referred to as the fluid mosaic model. The plasma membrane is composed of a bilayer of phospholipids, with their hydrophobic, fatty acid tails in contact with each other. The landscape of the membrane is studded with proteins, some of which span the membrane. Some of these proteins serve to transport materials into or out of the cell. Carbohydrates are attached to some of the proteins and lipids on the outward-facing surface of the membrane, forming complexes that function to identify the cell to other cells. The fluid nature of the membrane is due to temperature, the configuration of the fatty acid tails (some kinked by double bonds), the presence of cholesterol embedded in the membrane, and the mosaic nature of the proteins and protein-carbohydrate combinations, which are not firmly fixed in place. Plasma membranes enclose and define the borders of cells, but rather than being a static bag, they are dynamic and constantly in flux.

What is the term for a homogeneous mixture of two or more substances?

compound

element

saturation

solution

When rocks or other substances dissolve in water, they form a solution. A solution is a homogeneous mixture of two or more substances. The particles of a solution are mixed evenly throughout it. The particles are too small to be seen or to settle out. An example of a solution is salt water.

What is the simplest life cycle?

meiosis

glycolysis

eukaryot

haploid

The haploid life cycle is the simplest life cycle. Organisms with this life cycle, such as many protists and some fungi and algae, spend the majority of their life cycle as a haploid cell. In fact, the zygote is the only diploid cell. The zygote immediately undergoes meiosis, producing four haploid cells, which grow into haploid multicellular organisms. These organisms produce gametes by mitosis. The gametes fuse through a process called syngamy to produce diploid zygotes which undergo meiosis, continuing the life cycle.

Like mammals, birds have kidneys with juxtamedullary nephrons that specialize in conserving what?

air

food

blood

water

null

What is the range of all possible frequencies of radiation called?

particles spectrum

Difused Spectrum

vibrations spectrum

electromagnetic spectrum

Visible light constitutes only one of many types of electromagnetic radiation emitted from the sun and other stars. Scientists differentiate the various types of radiant energy from the sun within the electromagnetic spectrum. The electromagnetic spectrum is the range of all possible frequencies of radiation (Figure 8.11). The difference between wavelengths relates to the amount of energy carried by them.

What type of growth generally occurs only when a population is living under ideal conditions, yet cannot continue for very long?

logarithmic growth

analogous growth

negative growth

exponential growth

With exponential growth, the population starts out growing slowly. As population size increases, the growth rate also increases. The larger the population becomes, the more quickly it grows. This type of growth generally occurs only when a population is living under ideal conditions. However, it can’t continue for very long.

What is another term for flagella?

arthropods

tendrils

dendrites

pseudopods

Why are algae considered plant-like? The main reason is that they contain chloroplasts and produce food through photosynthesis . However, they lack many other structures of true plants. For example, algae do not have roots, stems, or leaves. Some algae also differ from plants in being motile. They may move with pseudopods or flagella. Although not plants themselves, algae were probably the ancestors of plants.

Because arthropod appendages are jointed, they can do what?

eat

rotate

fly

bend

Because arthropod appendages are jointed, they can bend. This makes them flexible. Jointed appendages on the body are usually used as legs for walking or jumping. Jointed appendages on the head may be modified for other purposes. Head appendages often include upper and lower jaws. Jaws are used for eating and may also be used for defense. Sensory organs such as eyes and antennae are also found on the head. You can see some of these head appendages on the bee in Figure below .

What is the main way that wind causes erosion?

decomposition

absorption

filtration

abrasion

Abrasion is the main way that wind causes erosion. The next lesson explains how glaciers cause erosion.

Each hydrogen atom follows the octet rule with how many pairs of electrons?

four

six

eight

one

The oxygen atom follows the octet rule with two pairs of bonding electrons and two lone pairs. Each hydrogen atom follows the octet rule with one bonding pair of electrons.

What type of acid is an organic compound that is built of small units called nucleotides?

carbolic acid

citric acid

boundary acid

nucleic acid

A nucleic acid is an organic compound, such as DNA or RNA, that is built of small units called nucleotides . Many nucleotides bind together to form a chain called a polynucleotide . The nucleic acid DNA (deoxyribonucleic acid) consists of two polynucleotide chains. The nucleic acid RNA (ribonucleic acid) consists of just one polynucleotide chain.

At what temperatures do crystals formed by covalent molecular solids melt at?

high

hot

scorching

low

Physical Properties of Ionic and Covalent Compounds In general, ionic and covalent compounds have different physical properties. Ionic compounds usually form hard crystalline solids that melt at rather high temperatures and are very resistant to evaporation. These properties stem from the characteristic internal structure of an ionic solid, illustrated schematically in part (a) in Figure 2.8 "Interactions in Ionic and Covalent Solids", which shows the three-dimensional array of alternating positive and negative ions held together by strong electrostatic attractions. In contrast, as shown in part (b) in Figure 2.8 "Interactions in Ionic and Covalent Solids", most covalent compounds consist of discrete molecules held together by comparatively weak intermolecular forces (the forces between molecules), even though the atoms within each molecule are held together by strong intramolecularcovalent bonds (the forces within the molecule). Covalent substances can be gases, liquids, or solids at room temperature and pressure, depending on the strength of the intermolecular interactions. Covalent molecular solids tend to form soft crystals that melt at rather low temperatures and evaporate relatively easily.

What is the name of the rigid layer that is found outside the cell membrane and surrounds the cell?

cell envelope

cellular shield

epidermis

cell wall

A cell wall is a rigid layer that is found outside the cell membrane and surrounds the cell. The cell wall contains not only cellulose and protein, but other polysaccharides as well. The cell wall provides structural support and protection. Pores in the cell wall allow water and nutrients to move into and out of the cell. The cell wall also prevents the plant cell from bursting when water enters the cell.

Who is widely known as the father of genetics?

francis crick

walter gehring

james watson

gregor mendel

The pea plant Pisum sativum has purple and white flowers. These flowered plants are not just pretty to look at. These plants led Gregor Mendel to unlock the secrets of heredity, beginning the field of genetics. For his efforts, Mendel is widely known as the Father of Genetics, even though he knew nothing of the genetic material, DNA. The laws he developed apply to all sexually reproducing life, and are the basis for beginning to understand many human diseases.

Protozoa that cause malaria are spread by a vector, entering the blood through the bite of what insect?

wasp

fire ant

housefly

mosquito

Protozoa that cause malaria are spread by a vector. They enter the blood through the bite of an infected mosquito. They live inside red blood cells. They cause overall body pain, fever, and fatigue. Malaria kills several million people each year. Most of the deaths occur in children.

One-dimensional sinusoidal waves show the relationship among wavelength, frequency, and what?

friction

velocity

motion

speed

Figure 6.2 One-dimensional sinusoidal waves show the relationship among wavelength, frequency, and speed. The wave with the shortest wavelength has the highest frequency. Amplitude is one-half the height of the wave from peak to trough.