NilsML/retriever_dataset · Datasets at Hugging Face

question stringlengths 14 399	distractor3 stringlengths 1 63	distractor1 stringlengths 1 57	distractor2 stringlengths 1 62	correct_answer stringlengths 1 67	support stringlengths 31 3.56k ⌀
What plant structures are the main avenues by which water evaporates from the sporophyte?	chloroplasts	veins	chlorophyll	stomata	null
Decomposers break down dead organisms into nutrients and what?	tissues	soil	fluids	gases	Decomposers break down dead organisms into nutrients and gases so that they can be used by other organisms.
What is the term for the use of technology to treat genetic disorders or change organisms so they are more useful to people?	nanotechnology	physiology	biology	biotechnology	Biotechnology is the use of technology to treat genetic disorders or change organisms so they are more useful to people. Methods include gene cloning. Applications include gene therapy and genetically modified food crops.
What science specialty, with a set of like-named scientific laws, refers to the study of energy and energy transfer involving physical matter?	chemistry	meteorology	geology	thermodynamics	6.3 \| The Laws of Thermodynamics By the end of this section, you will be able to: • Discuss the concept of entropy • Explain the first and second laws of thermodynamics Thermodynamics refers to the study of energy and energy transfer involving physical matter. The matter and its environment relevant to a particular case of energy transfer are classified as a system, and everything outside of that system is called the surroundings. For instance, when heating a pot of water on the stove, the system includes the stove, the pot, and the water. Energy is transferred within the system (between the stove, pot, and water). There are two types of systems: open and closed. An open system is one in which energy can be transferred between the system and its surroundings. The stovetop system is open because heat can be lost into the air. A closed system is one that cannot transfer energy to its surroundings. Biological organisms are open systems. Energy is exchanged between them and their surroundings, as they consume energystoring molecules and release energy to the environment by doing work. Like all things in the physical world, energy is subject to the laws of physics. The laws of thermodynamics govern the transfer of energy in and among all systems in the universe.
What type of tissue makes up the brain and the nerves that connect the brain to all parts of the body?	peripheral tissue	benign tissue	neurotransmitters	nervous tissue	Nervous tissue is made up of neurons, or nerve cells, that carry electrical messages. Nervous tissue makes up the brain and the nerves that connect the brain to all parts of the body.
Periodic refers to something that does what?	falls	dies	fail	repeat	Mendeleev’s table of the elements is called a periodic table because of its repeating pattern. Anything that keeps repeating is referred to as periodic. Other examples of things that are periodic include the monthly phases of the moon and the daily cycle of night and day. The term period refers to the interval between repetitions. In a periodic table, the periods are the rows of the table. In Mendeleev’s table, each period contains eight elements, and then the pattern repeats in the next row.
Blood is pumped from the heart, pushing open which valves?	thoracic and aortic	aortic and carotid	pulmonary and respiratory	pulmonary and aortic semilunar	Ventricular Systole Ventricular systole (see Figure 19.27) follows the depolarization of the ventricles and is represented by the QRS complex in the ECG. It may be conveniently divided into two phases, lasting a total of 270 ms. At the end of atrial systole and just prior to atrial contraction, the ventricles contain approximately 130 mL blood in a resting adult in a standing position. This volume is known as the end diastolic volume (EDV) or preload. Initially, as the muscles in the ventricle contract, the pressure of the blood within the chamber rises, but it is not yet high enough to open the semilunar (pulmonary and aortic) valves and be ejected from the heart. However, blood pressure quickly rises above that of the atria that are now relaxed and in diastole. This increase in pressure causes blood to flow back toward the atria, closing the tricuspid and mitral valves. Since blood is not being ejected from the ventricles at this early stage, the volume of blood within the chamber remains constant. Consequently, this initial phase of ventricular systole is known as isovolumic contraction, also called isovolumetric contraction (see Figure 19.27). In the second phase of ventricular systole, the ventricular ejection phase, the contraction of the ventricular muscle has raised the pressure within the ventricle to the point that it is greater than the pressures in the pulmonary trunk and the aorta. Blood is pumped from the heart, pushing open the pulmonary and aortic semilunar valves. Pressure generated by the left ventricle will be appreciably greater than the pressure generated by the right ventricle, since the existing pressure in the aorta will be so much higher. Nevertheless, both ventricles pump the same amount of blood. This quantity is referred to as stroke volume. Stroke volume will normally be in the range of 70–80 mL. Since ventricular systole began with an EDV of approximately 130 mL of blood, this means that there is still 50–60 mL of blood remaining in the ventricle following contraction. This volume of blood is known as the end systolic volume (ESV).
What term refers to a list of the elements that will replace the ones below them in single-replacement reactions?	Up series	growth series	probably series	activity series	Chemical reactivity trends are easy to predict when replacing anions in simple ionic compounds—simply use their relative positions on the periodic table. However, when replacing the cations, the trends are not as straightforward. This is partly because there are so many elements that can form cations; an element in one column on the periodic table may replace another element nearby, or it may not. A list called the activity series does the same thing the periodic table does for halogens: it lists the elements that will replace elements below them in single-replacement reactions. A simple activity series is shown below.
What cause many human diseases by killing host cells or disturbing their homeostasis?	bacteria	parasites	cancer	viruses	Viruses cause many human diseases by killing host cells or disturbing their homeostasis. Viruses are not affected by antibiotics. Several viral diseases can be treated with antiviral drugs or prevented with vaccines.
What two types of digestive systems do invertebrates have?	slow or complete	fast or slow	unstable or complete	incomplete or complete	Invertebrates have one of two types of digestive system: an incomplete or complete digestive system. Both are shown in Figure below . An incomplete digestive system consists of a digestive cavity with one opening. The single opening serves as both mouth and anus. A complete digestive system consists of a digestive tract with two openings. One opening is the mouth. The other is the anus.
What are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats?	arthropods	mammals	reptiles	amphibians	Amphibians are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats.
During exercise, the rate of blood returning to the heart does this?	reduces	remains stable	changes randomly	increases	Correlation Between Heart Rates and Cardiac Output Initially, physiological conditions that cause HR to increase also trigger an increase in SV. During exercise, the rate of blood returning to the heart increases. However as the HR rises, there is less time spent in diastole and consequently less time for the ventricles to fill with blood. Even though there is less filling time, SV will initially remain high. However, as HR continues to increase, SV gradually decreases due to decreased filling time. CO will initially stabilize as the increasing HR compensates for the decreasing SV, but at very high rates, CO will eventually decrease as increasing rates are no longer able to compensate for the decreasing SV. Consider this phenomenon in a healthy young individual. Initially, as HR increases from resting to approximately 120 bpm, CO will rise. As HR increases from 120 to 160 bpm, CO remains stable, since the increase in rate is offset by decreasing ventricular filling time and, consequently, SV. As HR continues to rise above 160 bpm, CO actually decreases as SV falls faster than HR increases. So although aerobic exercises are critical to maintain the health of the heart, individuals are cautioned to monitor their HR to ensure they stay within the target heart rate range of between 120 and 160 bpm, so CO is maintained. The target HR is loosely defined as the range in which both the heart and lungs receive the maximum benefit from the aerobic workout and is dependent upon age.
What is the pattern of spacing among individuals within the boundaries of the population?	equilibrium	frequency	diffusion	dispersion	null
What level is a feeding position in a food chain or web?	singular	neural	differentiation	trophic	Each food chain or food web has organisms at different trophic levels. A trophic level is a feeding position in a food chain or web. The trophic levels are identified in the food web in Figure above . All food chains and webs have at least two or three trophic levels, but they rarely have more than four trophic levels. The trophic levels are:.
What do most of the noble gas elements have in common?	four valence electrons	two valence electrons	zero valence electrons	eight valence electrons	Atoms can join together by forming a chemical bond, which is a very strong attraction between two atoms. Chemical bonds are formed when electrons in different atoms interact with each other to make an arrangement that is more stable than when the atoms are apart. What causes atoms to make a chemical bond with other atoms, rather than remaining as individual atoms? A clue comes by considering the noble gas elements, the rightmost column of the periodic table. These elements—helium, neon, argon, krypton, xenon, and radon—do not form compounds very easily, which suggests that they are especially stable as lone atoms. What else do the noble gas elements have in common? Except for helium, they all have eight valence electrons. Chemists have concluded that atoms are especially stable if they have eight electrons in their outermost shell. This useful rule of thumb is called the octet rule, and it is a key to understanding why compounds form.
What are the organisms that live in extreme conditions known as?	naturophiles	carotenoids	fibroblasts	extremophiles	Many archaeans are extremophiles. Extremophiles are organisms that live in extreme conditions. For example, some archaeans live around hydrothermal vents. A hydrothermal vent is a crack on the ocean floor. You can see one in Figure below . Boiling hot, highly acidic water pours out of the vent. These extreme conditions don't deter archaeans. They have evolved adaptations for coping with them. These conditions are like those on ancient Earth. This suggests that archaeans may have evolved very early in Earth's history.
Collision frequency is greater for what category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'?	contiguous	heterogeneous	analogous	homogeneous	Heterogeneous catalysts are easier to recover. Collision frequency is greater for homogeneous catalysts. Homogeneous catalysts are often more sensitive to temperature. Homogeneous catalysts are often more expensive. Saylor URL: http://www. saylor. org/books.
What does the pull of the moon's gravity on earth cause?	waves	earthquakes	storms	tides	Figure below shows why tides occur. The main cause of tides is the pull of the Moon’s gravity on Earth. The pull is greatest on whatever is closest to the Moon. Although the gravity pulls the land, only the water can move. As a result:.
A water molecule forms when oxygen (o) and _______ atoms react and are held together by covalent bonds?	steam	nitrogen	carbon	hydrogen (h)	An example of a chemical compound is water. A water molecule forms when oxygen (O) and hydrogen (H) atoms react and are held together by covalent bonds. Like other compounds, water always has the same chemical composition: a 2:1 ratio of hydrogen atoms to oxygen atoms. This is expressed in the chemical formula H 2 O. A model of a water molecule is shown in Figure below .
What force makes objects seem lighter in water?	gravity	resilient	surface tension	buoyant	Because of buoyant force, objects seem lighter in water. You may have noticed this when you went swimming and could easily pick up a friend or sibling under the water. Some of the person’s weight was countered by the buoyant force of the water.
What is the process by which the nucleus of a eukaryotic cell divides?	cytokinesis	meiosis	angiogenesis	mitosis	Mitosis is the process by which the nucleus of a eukaryotic cell divides. It happens in four phases: prophase, metaphase, anaphase, and telophase.
Iceland is made up of a series of?	earthquakes	glaciers	outcrops	volcanoes	A fissure eruption on a volcano in Iceland. The lava flows downhill and turns snow into steam. Iceland is made of a set of volcanoes that are the result of a hotspot that lies on a mid-ocean ridge. The island is the only location where the mid-ocean ridge can be seen above sea level. Icelandic volcanoes have made the news lately since some have shut down air traffic in parts of Europe.
What type of organism does not need oxygen for growth and dies in its presence?	symbiotic	acidic	aerobic	anaerobic	An anaerobic organism is any organism that does not need oxygen for growth and even dies in its presence. Obligate anaerobes will die when exposed to atmospheric levels of oxygen. Clostridium perfringens bacteria, which are commonly found in soil around the world, are obligate anaerobes. Infection of a wound by C. perfringens bacteria causes the disease gas gangrene. Obligate anaerobes use molecules other than oxygen as terminal electron acceptors.
What is the name of specialized organs that filter the lymph by percolation through a maze of connective tissue filled with white blood cells?	cochlea	alveoli	edema glands	lymph nodes	eventually diffuses back into the capillaries near the venules. The remaining 15% of blood plasma drains out from the interstitial fluid into nearby lymphatic vessels (Figure 40.18). The fluid in the lymph is similar in composition to the interstitial fluid. The lymph fluid passes through lymph nodes before it returns to the heart via the vena cava. Lymph nodes are specialized organs that filter the lymph by percolation through a maze of connective tissue filled with white blood cells. The white blood cells remove infectious agents, such as bacteria and viruses, to clean the lymph before it returns to the bloodstream. After it is cleaned, the lymph returns to the heart by the action of smooth muscle pumping, skeletal muscle action, and one-way valves joining the returning blood near the junction of the venae cavae entering the right atrium of the heart.
What are hydrocarbons most important use?	electricity	lightsource	food	fuel	Hydrocarbons have a wide variety of important uses, but their most important use is as fuels.
What protects tissues of the central nervous system from changes in ph?	sucrose ions	fatty ions	cerebrum	bicarbonate ions	Bicarbonate ions play an important role in neutralizing acids throughout the body. Bicarbonate ions are especially important for protecting tissues of the central nervous system from changes in pH. The central nervous system includes the brain, which is the body’s control center. If pH deviates too far from normal, the central nervous system cannot function properly. This can have a drastic effect on the rest of the body.
The air pressure is about 80% that of ________ pressure at sea level.	specific atmospheric	internal atmospheric	adverse atmospheric	standard atmospheric	The air pressure is about 80% that of standard atmospheric pressure at sea level. For significant figure purposes, the standard pressure of 760 mmHg has three significant figures.
Vertebrates - including fish, amphibians, reptiles, birds, and mammals - belong to what phylum?	animalia	angulata	nematota	chordata	Vertebrates are animals in Phylum Chordata. Modern vertebrates include fish, amphibians, reptiles, birds, and mammals. You can see examples of all these groups of vertebrates in Figure below .
In our wildflower population, the pool of what remains constant from one generation to the next?	genomes	DNA	eggs	genes	null
When a membrane uses energy to move a substance across it, what kind of transport is this?	inactive	fast	slow	active	x rms = 2Dt, where D is the diffusion constant, representative values of which are found in Table 12.2. • Osmosis is the transport of water through a semipermeable membrane from a region of high concentration to a region of low concentration. • Dialysis is the transport of any other molecule through a semipermeable membrane due to its concentration difference. • Both processes can be reversed by back pressure. • Active transport is a process in which a living membrane expends energy to move substances across it.
An electrostatic attraction between two ions that have exchanged what?	protons	neutrons	quasars	electrons	An electrostatic attraction between two ions that have exchanged electrons.
During what part of a person's development are they generally at their physical peak?	senility	late adulthood	infancy	early adulthood	Early adulthood starts at age 18 or 21. It continues until the mid-30s. During early adulthood, people are at their physical peak. They are also usually in good health. The ability to have children is greatest during early adulthood, as well. This is the stage of life when most people complete their education. They are likely to begin a career or take a full-time job. Many people also marry and start a family during early adulthood.
What type of movement involves sluggish segmentation, primarily in the transverse and descending colons?	accompanying contraction	gasutral contraction	photoreactive contraction	haustral contraction	Mechanical Digestion In the large intestine, mechanical digestion begins when chyme moves from the ileum into the cecum, an activity regulated by the ileocecal sphincter. Right after you eat, peristalsis in the ileum forces chyme into the cecum. When the cecum is distended with chyme, contractions of the ileocecal sphincter strengthen. Once chyme enters the cecum, colon movements begin. Mechanical digestion in the large intestine includes a combination of three types of movements. The presence of food residues in the colon stimulates a slow-moving haustral contraction. This type of movement involves sluggish segmentation, primarily in the transverse and descending colons. When a haustrum is distended with chyme, its muscle contracts, pushing the residue into the next haustrum. These contractions occur about every 30 minutes, and each last about 1 minute. These movements also mix the food residue, which helps the large intestine absorb water. The second type of movement is peristalsis, which, in the large intestine, is slower than in the more proximal portions of the alimentary canal. The third type is a mass movement. These strong waves start midway through the transverse colon and quickly force the contents toward the rectum. Mass movements usually occur three or four times per day, either while you eat or immediately afterward. Distension in the stomach and the breakdown products of digestion in the small intestine provoke the gastrocolic reflex, which increases motility, including mass movements, in the colon. Fiber in the diet both softens the stool and increases the power of colonic contractions, optimizing the activities of the colon.
Vertebrates evolved from primitive forms of which creature?	eukaryotes	gastropods	cephalopods	chordates	Vertebrates evolved from primitive chordates. This occurred about 550 million years ago. The earliest vertebrates may have been jawless fish, like the hagfish in Figure below . Vertebrates evolved a backbone to replace the notochord after the embryo stage. They also evolved a cranium, or bony skull, to enclose and protect the brain.
What does the aqueous fluid between the chloroplast membrane and the grana known as?	blood	plasma	water	stroma	Both chloroplasts and photosynthetic bacteria contain grana, neat stacks of flattened sac-shaped membrane compartments called thylakoids . Thylakoids can be considered a sub-organelle within the chloroplast. Between the chloroplast membrane and the grana is an aqueous fluid known as stroma . Thylakoids, especially the thylakoid membrane, organize patterns of proteins and other molecules which conduct photosynthesis, as shown in Figure below . In addition to enzymes, two basic types of molecules - pigments and electron carriers – are significant in this process. You can take a video tour of a chloroplast at Encyclopedia Britannica: Chloroplast : http://www. britannica. com/EBchecked/media/16440/Chloroplasts-circulate-within-plant-cells .
When a hypothesis is repeatedly confirmed, what can it then become?	evolution	Thesis	study	theory	When a hypothesis is confirmed repeatedly, it eventually becomes a theory – a general principle that is offered to explain natural phenomena. Note a key word – explanation. The theory offers a description of why something happens. A law, on the other hand, is a statement that is always true, but does not explain why. The law of gravity says a rock will fall when dropped, but does not explain why (gravitational theory is very complex and incomplete at present). The kinetic-molecular theory of gases, on the other hand, tells what happens when a gas is heated in a closed container (the pressure increases), but also explains why (the motions of the gas molecules are increased due to the change in temperature). Theories do not get “promoted” to laws because laws do not answer the “why” question.
Using a hammer to remove a nail changes both the direction and strength of the what?	static energy	kinetic energy	gravity	applied force	Using a hammer to remove a nail changes both the direction and strength of the applied force. Where is the fulcrum of the hammer when it is used in this way?.
Through which process are plants able to make their own food?	metabolism	cell division	glycolysis	photosynthesis	null
What kind of waves are sound waves?	spinning	External	internal	mechanical	A: It wouldn’t unless the vibrations were carried by another medium. Sound waves are mechanical waves, so they can travel only though matter and not through empty space.
The protein without the prosthetic group is known as the what?	spicule	xerophyte	monoprotein	apoprotein	As we will return to later, proteins are functional entities, composed of polypeptides and prosthetic group. The prosthetic group is essential for normal protein function. The protein without the prosthetic group is known as the apoprotein. biofundamentals – coreBIO.
What connections allow heterocysts to transport fixed nitrogen to neighboring cells and to receive carbohydrates?	peptide	neurons	heterogeneity	intercellular	null
The classes anthozoa, scyphozoa, cubozoa, and hydrozoa make up what phylum?	poriferia	crinoids	mollusca	cnidaria	differentiated cell types in each tissue layer, such as nerve cells, enzyme-secreting cells, and nutrient-absorbing cells, as well as intercellular connections between the cells. However, organs and organ systems are not present in this phylum. The nervous system is primitive, with nerve cells scattered across the body in a network. The function of the nerve cells is to carry signals from sensory cells and to contractile cells. Groups of cells in the nerve net form nerve cords that may be essential for more rapid transmission. Cnidarians perform extracellular digestion, with digestion completed by intracellular digestive processes. Food is taken into the gastrovascular cavity, enzymes are secreted into the cavity, and the cells lining the cavity absorb the nutrient products of the extracellular digestive process. The gastrovascular cavity has only one opening that serves as both a mouth and an anus (an incomplete digestive system). Like the sponges, Cnidarian cells exchange oxygen, carbon dioxide, and nitrogenous wastes by diffusion between cells in the epidermis and gastrodermis with water. Cnidarian Diversity The phylum Cnidaria contains about 10,000 described species divided into four classes: Anthozoa, Scyphozoa, Cubozoa, and Hydrozoa. The class Anthozoa includes all cnidarians that exhibit a sessile polyp body plan only; in other words, there is no medusa stage within their life cycle. Examples include sea anemones, sea pens, and corals, with an estimated number of 6,100 described species. Sea anemones are usually brightly colored and can attain a size of 1.8 to 10 cm in diameter. These animals are usually cylindrical in shape and are attached to a substrate. A mouth opening is surrounded by tentacles bearing cnidocytes (Figure 15.12).
Where does waste enter the large intestine from?	liver	the small tissue	kidneys	the small intestine	The large intestine is a wide tube that connects the small intestine with the anus. In adults, it is about five feet long. Waste enters the large intestine from the small intestine in a liquid state. As the waste moves through the large intestine, excess water is absorbed from it. After the excess water is absorbed, the remaining solid waste is called feces.
What do different soil horizons show different amounts of?	evolution	distortion	secretion	alteration	Soil horizons are layers within a soil. Different soil horizons show different amounts of alteration.
What is the main source of energy for your body?	fats	proteins	vitamins	carbohydrates	Carbohydrates, proteins, and lipids are categories of organic compounds. They give your body energy, though carbohydrates are the main source of energy. Proteins provide building materials, such as amino acids to build your own proteins. Proteins, vitamins, and minerals also help control body processes. Carbohydrates include sugars such as the glucose made by photosynthesis. Often glucose is stored in large molecules such as starch. Proteins are found in foods like meats and nuts. Lipids includes fats and oils. Though you should stay away from many types of fats, others are needed by your body. Important vitamins include vitamins A, B (multiple types) C, D, and E. Important minerals include calcium and potassium. What should you drink to get calcium? Milk is a good source.
What are thin, very small tail-like projections that extend outward from the cell body that allow protists to move?	fins	antennae	notochords	cilia	The ciliates are protists that move by using cilia. Cilia are thin, very small tail-like projections that extend outward from the cell body. Cilia beat back and forth, moving the protist along. Paramecium has cilia that propel it.
Earthquakes, which may occur on california’s abundant faults, can also trigger what?	floods	Waves	avalanches	landslides	Some communities have developed landslide warning systems. Around San Francisco Bay, the National Weather Service and the U. S. Geological Survey use rain gauges to monitor soil moisture. If soil becomes saturated, the weather service issues a warning. Earthquakes, which may occur on California’s abundant faults, can also trigger landslides.
In which way do particles of water move in deep water?	ellipses	currents	parabolas	circles	In deep water, particles of water just move in circles. They don’t actually move closer to shore with the energy of the waves. However, near the shore where the water is shallow, the waves behave differently. They start to drag on the bottom, creating friction (see Figure below ). The friction slows down the bottoms of the waves, while the tops of the waves keep moving at the same speed. This causes the waves to get steeper until they topple over and crash on the shore. The crashing waves carry water onto the shore as surf.
What is the name of the study of heat engines?	Chemical dynamics	chemistry	biology	thermodynamics	Thermodynamics is the study of heat engines. Any engine or power plant obeys the laws of thermodynamics. The first law of thermodynamics is a statement of conservation of energy. Total energy, including heat, is conserved in any process and in the complete cycle of a heat engine. The second law of thermodynamics as it applies to heat engines gives an absolute limit on the efficiency of any heat engine that goes through repetitious cycles.
Mechanical waves can only trave through what?	water	light	air	matter	The energy of a mechanical wave can travel only through matter. The matter through which the wave travels is called the medium ( plural , media). The medium in the water wave pictured above is water, a liquid. But the medium of a mechanical wave can be any state of matter, even a solid.
If you examine eyeglasses for nearsighted people, you will find the lenses are thinnest in the center and of what shape?	square	convex	asymmetrical	concave	Discussion The negative power indicates a diverging (or concave) lens, as expected. The spectacle produces a case 3 image closer to the eye, where the person can see it. If you examine eyeglasses for nearsighted people, you will find the lenses are thinnest in the center. Additionally, if you examine a prescription for eyeglasses for nearsighted people, you will find that the prescribed power is negative and given in units of diopters.
What do you call air flowing over earth’s surface?	air pressure	gas	steam	wind	Air always flows from an area of higher pressure to an area of lower pressure. Air flowing over Earth’s surface is called wind . The greater the difference in pressure, the stronger the wind blows.
What three particles make up most atoms?	neutrons, protons and radii	protons, electrons and nucleus	micrometres , electrons and neutrons	protons, electrons and neutrons	A neutron is one of three main particles that make up the atom. The other two particles are the proton and electron. Atoms of all elements—except for most atoms of hydrogen—have neutrons in their nucleus. The nucleus is the small, dense region at the center of an atom where protons are also found. Atoms generally have about the same number of neutrons as protons. For example, all carbon atoms have six protons and most also have six neutrons. A model of a carbon atom is shown in the Figure below . For an excellent video explaining the structure of atoms, including neutrons, go to this URL:.
How can one dimensional vectors be added?	exponentially	incrementally	sequentially	arithmetically	Vectors that are in one dimension can be added arithmetically.
What is caused by the reaction of nonmetal oxides with water in the atmosphere?	yellow rain	ozone rain	carbon rain	acid rain	Acid rain is caused by the reaction of nonmetal oxides with water in the atmosphere. One such reaction involves nitrogen dioxide (NO2) and produces nitric acid (HNO3): 3NO2 + H2O → 2HNO3 + NO If 1.82 × 1013 g of NO2 enter the atmosphere every year due to human activities, potentially how many grams of HNO3 can be produced annually?.
Into how many basic regions can the aquatic biome be broken down?	five	six	One	two	null
The top of the saturated rock layer is called what?	calcified layer	sand layer	compressed layer	water table	The top of the saturated rock layer above ( Figure above ) is called the water table . The water table isn’t like a real table. It doesn’t remain firmly in one place. Instead, it rises or falls, depending on how much water seeps down from the surface. The water table is higher when there is a lot of rain, and it is lower when the weather is dry.
Which field studies how to tailor medical treatments to our genetic profiles?	proteomics	immunology	metagenomics	pharmacogenomics	We know that, thanks to our DNA, each of us is a little bit different. Some of those differences are obvious, like eye and hair color. Others are not so obvious, like how our bodies react to medication. Researchers are beginning to look at how to tailor medical treatments to our genetic profiles, in a relatively new field called pharmacogenomics . Some of the biggest breakthroughs have been in cancer treatment. For additional information on this “personalized medicine,” listen to http://www. kqed. org/quest/radio/personalized-medicine and see http://www. kqed. org/quest/blog/2009/09/11/reporters-notes-personalized-medicine/ .
Research that focuses on understanding basic properties and processes without concern for the usefulness of this understanding is known as what kind of research?	focused research	disconnected research	applied research	pure research	Pure research focuses on understanding basic properties and processes.
Cells of what category of organisms can be organized at the level of cells, tissues, organs, and organ systems?	complex	biomolecular	intricate	multicellular	Cells can exist independently as single-celled organisms or with other cells as multicellular organisms. Cells of a multicellular organism can be organized at the level of cells, tissues, organs, and organ systems.
What property of materials describes the ease in which they can be molded into thin sheets?	rigidity	plasticity	permeability	malleability	A physical property is a characteristic of a substance that can be observed or measured without changing the identity of the substance. Silver is a shiny metal that conducts electricity very well. It can be molded into thin sheets, a property called malleability. Salt is dull and brittle and conducts electricity when it has been dissolved into water, which it does quite easily. Physical properties of matter include color, hardness, malleability, solubility, electrical conductivity, density, melting points , and boiling points .
What do you call materials that have low resistance to electric current?	good insulator	electromagnets	poor conductors	electric conductors	Materials that have low resistance to electric current are called electric conductors . Many metals—including copper, aluminum, and steel—are good conductors of electricity. The outer electrons of metal atoms are loosely bound and free to move, allowing electric current to flow. Water that has even a tiny amount of impurities is an electric conductor as well.
What is the term for the transfer of heat by a current?	diffusion	conduction	radiation	convection	Convection is the transfer of heat by a current. Convection happens in a liquid or a gas. Air near the ground is warmed by heat radiating from Earth's surface. The warm air is less dense, so it rises. As it rises, it cools. The cool air is dense, so it sinks to the surface. This creates a convection current ( Figure below ). Convection is the most important way that heat travels in the atmosphere.
Arterioles receive blood from arteries, which are vessels with a much larger lumen. as their own lumen averages just 30 micrometers or less, arterioles are critical in slowing down—or resisting—blood flow. the arterioles can also constrict or dilate, which varies their what?	advantage	osmosis	gravity	resistance	Chapter 20 1 Water. 3 A 5 C 7 C 9 A 11 D 13 B 15 A 17 C 19 A 21 C 23 D 25 D 27 C 28 Arterioles receive blood from arteries, which are vessels with a much larger lumen. As their own lumen averages just 30 micrometers or less, arterioles are critical in slowing down—or resisting—blood flow. The arterioles can also constrict or dilate, which varies their resistance, to help distribute blood flow to the tissues. 30 This is a venule. 32 People who stand upright all day and are inactive overall have very little skeletal muscle activity in the legs. Pooling of blood in the legs and feet is common. Venous return to the heart is reduced, a condition that in turn reduces cardiac output and therefore oxygenation of tissues throughout the body. This could at least partially account for the patient’s fatigue and shortness of breath, as well as her “spaced out” feeling, which commonly reflects reduced oxygen to the brain. 34 False. The plasma proteins suspended in blood cannot cross the semipermeable capillary cell membrane, and so they remain in the plasma within the vessel, where they account for the blood colloid osmotic pressure. 36 Nitric oxide is a very powerful local vasodilator that is important in the autoregulation of tissue perfusion. If it were not broken down very quickly after its release, blood flow to the region could exceed metabolic needs. 38 The gonadal veins drain the testes in males and the ovaries in females. 40 Angiogenesis inhibitors are drugs that inhibit the growth of new blood vessels. They can impede the growth of tumors by limiting their blood supply and therefore their access to gas and nutrient exchange.
What is the circular center of a hurricane better known as?	the focus	the epicenter	the nose	the eye	At the center of a hurricane is a small area where the air is calm and clear. This is called the eye of the hurricane ( Figure below ). The eye forms at the low-pressure center of the hurricane. Air in the eye rises upward.
Are most glaciers currently growing or shrinking?	no change	growing	freezing	shrinking	Glaciers are not static; they grow, they move and they shrink. Currently, most glaciers are shrinking.
What kind of model - which includes producers, consumers and decomposers - shows the interactions between organisms across trophic levels?	organic web	interdepence web	fuel web	food web	Figure 20.6 This food web shows the interactions between organisms across trophic levels. Arrows point from an organism that is consumed to the organism that consumes it. All the producers and consumers eventually become nourishment for the decomposers (fungi, mold, earthworms, and bacteria in the soil). (credit "fox": modification of work by Kevin Bacher, NPS; credit "owl": modification of work by John and Karen Hollingsworth, USFWS; credit "snake": modification of work by Steve Jurvetson; credit "robin": modification of work by Alan Vernon; credit "frog": modification of work by Alessandro Catenazzi; credit "spider": modification of work by "Sanba38"/Wikimedia Commons; credit "centipede": modification of work by “Bauerph”/Wikimedia Commons; credit "squirrel": modification of work by Dawn Huczek; credit "mouse": modification of work by NIGMS, NIH; credit "sparrow": modification of work by David Friel; credit "beetle": modification of work by Scott Bauer, USDA Agricultural Research Service; credit "mushrooms": modification of work by Chris Wee; credit "mold": modification of work by Dr. Lucille Georg, CDC; credit "earthworm": modification of work by Rob Hille; credit "bacteria": modification of work by Don Stalons, CDC).
The multifidus muscle of the lumbar region helps extend and laterally flex this?	knee	forearm	pelvic muscle	vertebal column	are associated. The semispinalis muscles include the semispinalis capitis, the semispinalis cervicis, and the semispinalis thoracis. The multifidus muscle of the lumbar region helps extend and laterally flex the vertebral column. Important in the stabilization of the vertebral column is the segmental muscle group, which includes the interspinales and intertransversarii muscles. These muscles bring together the spinous and transverse processes of each consecutive vertebra. Finally, the scalene muscles work together to flex, laterally flex, and rotate the head. They also contribute to deep inhalation. The scalene muscles include the anterior scalene muscle (anterior to the middle scalene), the middle scalene muscle (the longest, intermediate between the anterior and posterior scalenes), and the posterior scalene muscle (the smallest, posterior to the middle scalene).
What does k stand for on the periodic table?	calcium	aluminum	magnesium	potassium	Q: The table shown in the Figure above is called the periodic table of the elements. Each symbol stands for a different element. What do you think the symbol K stands for?.
Beta decay occurs when a nucleus has too few of what relative to protons?	nuclei	protons	electrons	neutrons	Beta decay occurs when a nucleus is unstable because it has too many or too few neutrons relative to protons. The nucleus emits a beta particle and energy. A beta particle is either an electron (beta-minus decay) or a positron (beta-plus decay).
Trees have woody stems covered with what?	shells	larvae	rust	bark	Trees have woody stems covered with bark.
What prevents an object from moving in a straight line at a constant speed?	matter	weight	friction	force	Newton’s first law implies that an object oscillating back and forth is experiencing forces. Without force, the object would move in a straight line at a constant speed rather than oscillate. Consider, for example, plucking a plastic ruler to the left as shown in Figure 16.2. The deformation of the ruler creates a force in the opposite direction, known as a restoring force. Once released, the restoring force causes the ruler to move back toward its stable equilibrium position, where the net force on it is zero. However, by the time the ruler gets there, it gains momentum and continues to move to the right, producing the opposite deformation. It is then forced to the left, back through equilibrium, and the process is repeated until dissipative forces dampen the motion. These forces remove mechanical energy from the system, gradually reducing the motion until the ruler comes to rest. The simplest oscillations occur when the restoring force is directly proportional to displacement. When stress and strain were covered in Newton’s Third Law of Motion, the name was given to this relationship between force and displacement was Hooke’s law:.
The effect of acetylcholine in heart muscle is inhibitory rather than what?	exofactory	neurotransmitter	olfactory	excitatory	null
What is the division of the cytoplasm in eukaryotic cells?	metamorphosis	electrolysis	andronisis	cytokinesis	The second major step is cytokinesis . As in prokaryotic cells, the cytoplasm must divide. Cytokinesis is the division of the cytoplasm in eukaryotic cells, resulting in two genetically identical daughter cells.
The white of an egg becomes opaque when cooked because what are insoluble and solidify?	fatty acids	acetic proteins	calcium molecules	denatured proteins	null
What kind of plants lack xylem or phloem to transport nutrients, water, and food?	spicule	single-celled	trichina	nonvascular	Nonvascular plants evolved first. They are distinct from the algae because they keep the embryo inside of the reproductive structure after fertilization. These plants do not have vascular tissue, xylem or phloem, to transport nutrients, water, and food. Examples include mosses, liverworts, and hornworts. Without vascular tissue, these plants do not grow very tall.
Exemplified by baring teeth, what type of displays are common in the animal kingdom, and sometimes serve as a 'bluff'?	sexual	passive	defensive	aggressive	incorrectly or a proper response is not given, the mating ritual is abandoned and the mating attempt will be unsuccessful. The mating display of the common stork is shown in Figure 45.37. Aggressive displays are also common in the animal kingdom. An example is when a dog bares its teeth when it wants another dog to back down. Presumably, these displays communicate not only the willingness of the animal to fight, but also its fighting ability. Although these displays do signal aggression on the part of the sender, it is thought that these displays are actually a mechanism to reduce the amount of actual fighting that occurs between members of the same species: they allow individuals to assess the fighting ability of their opponent and thus decide whether it is “worth the fight. ” The testing of certain hypotheses using game theory has led to the conclusion that some of these displays may overstate an animal’s actual fighting ability and are used to “bluff” the opponent. This type of interaction, even if “dishonest,” would be favored by natural selection if it is successful more times than not.
The preferred phase a substance adopts can change with temperature. at low temperatures, most substances are solids (only helium is predicted to be a liquid at absolute zero). as the temperature increases, those substances with very weak intermolecular forces become gases directly in a process called this?	Freezing Point	speciation	vaporization	sublimation	The preferred phase a substance adopts can change with temperature. At low temperatures, most substances are solids (only helium is predicted to be a liquid at absolute zero). As the temperature increases, those substances with very weak intermolecular forces become gases directly (in a process called sublimation, which will be discussed in Section 10.2 "Phase Transitions: Melting, Boiling, and Subliming"). Substances with weak interactions can become liquids as the temperature increases. As the temperature increases even more, the individual particles will have so much energy that the intermolecular forces are overcome, so the particles separate from each other, and the substance becomes a gas (assuming that their chemical bonds are not so weak that the compound decomposes from the high temperature). Although is it difficult to predict the temperature ranges for which solid, liquid, or gas is the preferred phase for any random substance, all substances progress from solid to liquid to gas in that order as temperature increases.
What pigment do slow fibers contain?	iron	melolin	hemoglobin	myoglobin	Which of the following statements is true? a. Fast fibers have a small diameter. Fast fibers contain loosely packed myofibrils. Fast fibers have large glycogen reserves. Fast fibers have many mitochondria. Which of the following statements is false? a. Slow fibers have a small network of capillaries. Slow fibers contain the pigment myoglobin. Slow fibers contain a large number of mitochondria. Slow fibers contract for extended periods. Cardiac muscles differ from skeletal muscles in that they ________. are striated b. utilize aerobic metabolism.
What are clathrin, copi and copii types of?	artery coats	replication coats	pathogen coats	vesicle coats	The vesicle coat selects specific proteins as cargo. It selects cargo proteins by binding to sorting signals. These complexes cluster in the membrane, forming a vesicle buds, or coated pit . There are three types of vesicle coats: clathrin , COPI and COPII. Clathrin coats are found on vesicles trafficking between the Golgi and plasma membrane, the Golgi and endosomes, and the plasma membrane and endosomes. COPI ( coat protein complex) coated vesicles are responsible for transport from the cis -Golgi to the ER (retrograde transport), while COPII coated vesicles are responsible for transport from the ER to the Golgi (anterograde transport). Low-density lipoprotein (LDL) receptors aggregate in clathrin coated pits prior to internalization.
What is the name for the force that attracts water molecules to other polar substances?	aeration	osmosis	diffusion	adhesion	null
All alkaline earth metals have similar properties because they all have two what?	caesium electrons	balanced electrons	transitions electrons	valence electrons	All alkaline Earth metals have similar properties because they all have two valence electrons. They readily give up their two valence electrons to achieve a full outer energy level, which is the most stable arrangement of electrons. As a result, they are very reactive, although not quite as reactive as the alkali metals in group 1. For example, alkaline Earth metals will react with cold water, but not explosively as alkali metals do. Because of their reactivity, alkaline Earth metals never exist as pure substances in nature. Instead, they are always found combined with other elements.
A solenoid or coil wrapped around iron or certain other metals can form what kind of magnet?	polarized magnet	permanent magnet	superconductor	electromagnet	An electromagnet is a solenoid wrapped around a bar of iron or other ferromagnetic material. The magnetic field of the solenoid magnetizes the iron bar.
Is the yolk more or less concentrated toward the animal pole?	no change	more concentrated	same concentrated	less concentrated	null
What are the location where bones come together?	fingers	muscles	Knees	joints	The adult human body has 206 bones, and with the exception of the hyoid bone in the neck, each bone is connected to at least one other bone. Joints are the location where bones come together. Many joints allow for movement between the bones. At these joints, the articulating surfaces of the adjacent bones can move smoothly against each other. However, the bones of other joints may be joined to each other by connective tissue or cartilage. These joints are designed for stability and provide for little or no movement. Importantly, joint stability and movement are related to each other. This means that stable joints allow for little or no mobility between the adjacent bones. Conversely, joints that provide the most movement.
What term denotes lower levels of exposure, for instance to radiation, over a longer period of time?	excess exposure	non-exposure	recent exposure	chronic exposure	Exposure gives an indication of the amount of radiation that travels through the air. Two factors influence the amount of exposure a person may receive – time and intensity. Acute exposure indicates a large amount of radiation received over a short period of time. Chronic exposure deals with lower levels of exposure over a longer period of time. Dose equivalence combines the amount of radiation received and the medical effect of that radiation. Calculations of exposure and dose equivalence are complicated and will not be pursued at this time.
What causes water molecules to stay close to each other?	friction	oxidation	surface tension	hydrogen bonding	null
What is the main cause of recent global warming?	insect overpopulation	ice ages	solar flares	human beings	Natural processes caused earlier climate changes. Human beings are the main cause of recent global warming.
In solids, particles can't overcome the force of attraction between them because they lack what?	momentum	gravity	residual energy	kinetic energy	In solids, particles don’t have enough kinetic energy to overcome the force of attraction between them. The particles are packed closely together and cannot move around. All they can do is vibrate. This explains why solids have a fixed volume and shape.
What are the organelles where the process of photosynthesis takes place in plants and algae.	ribosomes	fibroblasts	mitochondria	chloroplasts	Chloroplasts are the organelles where the process of photosynthesis takes place in plants and algae.
What process occurs when two alleles are expressed equally in the phenotype of the heterozygote?	codependence	pollenation	fertilization	codominance	Codominance occurs when both alleles are expressed equally in the phenotype of the heterozygote. The red and white flower in the figure has codominant alleles for red petals and white petals.
Magnetic poles always occur in pairs - what are the names of each pole?	southwest and south	prime and equator	tropic and arctic	north and south	• Like poles repel and unlike poles attract. • Magnetic poles always occur in pairs of north and south—it is not possible to isolate north and south poles.
Anemia is a disease that affects what?	kidney	brain	heart	blood	Red meat, legumes, and spinach are all good sources of iron. Getting enough iron in your diet is important to prevent anemia. Anemia is a blood disease that causes you to feel weak and tired. Although anemia is caused by a nutrient deficiency, other blood diseases are genetic diseases, or forms of cancer.
The end of a pine tree branch bears the male cones that produce what?	needles	spores	flowers	pollen	The end of a pine tree branch bears the male cones that produce the pollen.
What is the material inside the cell membrane called?	chloroplasm	mucus	cerebellum	cytoplasm	Cytoplasm is the material inside the cell membrane. It includes a watery substance called cytosol. Besides water, cytosol contains enzymes and other substances. Cytoplasm also includes other cell structures suspended in the cytosol.
The energy stored in the organic molecules of food ultimately comes from where?	plant	earth	ocean	sun	null
Sulfur dioxide produced by burning coal is the leading cause of what deadly phenomenon?	dioxide rain	hail	carbon rain	acid rain	Another problem with coal is that most coal contains sulfur. As it burns, the sulfur goes into the air as sulfur dioxide. Sulfur dioxide is the main cause of acid rain. Acid rain can be deadly to plants, animals, and whole ecosystems. Burning coal also puts a large number of small solid particulates into the air. These particles are dangerous to people, especially those who have asthma. People with asthma may end up in the hospital on days when particulate pollution is high.
When an eagle, a land eater, goes and gets fish from the sea, as well, its called?	descending food web	overlapping food source	food chain mixing	overlapping food web	Food webs also overlap. For example, an eagle is part of a land food web. But it might go to the sea to grab a fish. That fish is part of a marine food web.
Where the axon emerges from the cell body, there is a special region referred to as the what?	cellular hillock	axosomatic synapse	dendrite	axon hillock	Where the axon emerges from the cell body, there is a special region referred to as the axon hillock. This is a tapering of the cell body toward the axon fiber. Within the axon hillock, the cytoplasm changes to a solution of limited components called axoplasm. Because the axon hillock represents the beginning of the axon, it is also referred to as the initial segment. Many axons are wrapped by an insulating substance called myelin, which is actually made from glial cells. Myelin acts as insulation much like the plastic or rubber that is used to insulate electrical wires. A key difference between myelin and the insulation on a wire is that there are gaps in the myelin covering of an axon. Each gap is called a node of Ranvier and is important to the way that electrical signals travel down the axon. The length of the axon between each gap, which is wrapped in myelin, is referred to as an axon segment. At the end of the axon is the axon terminal, where there are usually several branches extending toward the target cell, each of which ends in an enlargement called a synaptic end bulb. These bulbs are what make the connection with the target cell at the synapse.
The specialized study of the motion of objects that are atomic/subatomic in size is called what?	enthalpy	string theory	atomic mechanics	quantum mechanics	The study of motion of large objects such as baseballs is called mechanics, or more specifically classical mechanics. Because the quantum nature of the electron and other tiny particles moving at high speeds, classical mechanics is inadequate to accurately describe their motion. Quantum mechanics is the study of the motion of objects that are atomic or subatomic in size and thus demonstrate wave-particle duality. In classical mechanics, the size and mass of the objects involved effectively obscures any quantum effects so that such objects appear to gain or lose energies in any amounts. Particles whose motion is described by quantum mechanics gain or lose energy in the small pieces called quanta .

What plant structures are the main avenues by which water evaporates from the sporophyte?

chloroplasts

veins

chlorophyll

stomata

null

Decomposers break down dead organisms into nutrients and what?

tissues

soil

fluids

gases

Decomposers break down dead organisms into nutrients and gases so that they can be used by other organisms.

What is the term for the use of technology to treat genetic disorders or change organisms so they are more useful to people?

nanotechnology

physiology

biology

biotechnology

Biotechnology is the use of technology to treat genetic disorders or change organisms so they are more useful to people. Methods include gene cloning. Applications include gene therapy and genetically modified food crops.

What science specialty, with a set of like-named scientific laws, refers to the study of energy and energy transfer involving physical matter?

chemistry

meteorology

geology

thermodynamics

6.3 | The Laws of Thermodynamics By the end of this section, you will be able to: • Discuss the concept of entropy • Explain the first and second laws of thermodynamics Thermodynamics refers to the study of energy and energy transfer involving physical matter. The matter and its environment relevant to a particular case of energy transfer are classified as a system, and everything outside of that system is called the surroundings. For instance, when heating a pot of water on the stove, the system includes the stove, the pot, and the water. Energy is transferred within the system (between the stove, pot, and water). There are two types of systems: open and closed. An open system is one in which energy can be transferred between the system and its surroundings. The stovetop system is open because heat can be lost into the air. A closed system is one that cannot transfer energy to its surroundings. Biological organisms are open systems. Energy is exchanged between them and their surroundings, as they consume energystoring molecules and release energy to the environment by doing work. Like all things in the physical world, energy is subject to the laws of physics. The laws of thermodynamics govern the transfer of energy in and among all systems in the universe.

What type of tissue makes up the brain and the nerves that connect the brain to all parts of the body?

peripheral tissue

benign tissue

neurotransmitters

nervous tissue

Nervous tissue is made up of neurons, or nerve cells, that carry electrical messages. Nervous tissue makes up the brain and the nerves that connect the brain to all parts of the body.

Periodic refers to something that does what?

falls

dies

fail

repeat

Mendeleev’s table of the elements is called a periodic table because of its repeating pattern. Anything that keeps repeating is referred to as periodic. Other examples of things that are periodic include the monthly phases of the moon and the daily cycle of night and day. The term period refers to the interval between repetitions. In a periodic table, the periods are the rows of the table. In Mendeleev’s table, each period contains eight elements, and then the pattern repeats in the next row.

Blood is pumped from the heart, pushing open which valves?

thoracic and aortic

aortic and carotid

pulmonary and respiratory

pulmonary and aortic semilunar

Ventricular Systole Ventricular systole (see Figure 19.27) follows the depolarization of the ventricles and is represented by the QRS complex in the ECG. It may be conveniently divided into two phases, lasting a total of 270 ms. At the end of atrial systole and just prior to atrial contraction, the ventricles contain approximately 130 mL blood in a resting adult in a standing position. This volume is known as the end diastolic volume (EDV) or preload. Initially, as the muscles in the ventricle contract, the pressure of the blood within the chamber rises, but it is not yet high enough to open the semilunar (pulmonary and aortic) valves and be ejected from the heart. However, blood pressure quickly rises above that of the atria that are now relaxed and in diastole. This increase in pressure causes blood to flow back toward the atria, closing the tricuspid and mitral valves. Since blood is not being ejected from the ventricles at this early stage, the volume of blood within the chamber remains constant. Consequently, this initial phase of ventricular systole is known as isovolumic contraction, also called isovolumetric contraction (see Figure 19.27). In the second phase of ventricular systole, the ventricular ejection phase, the contraction of the ventricular muscle has raised the pressure within the ventricle to the point that it is greater than the pressures in the pulmonary trunk and the aorta. Blood is pumped from the heart, pushing open the pulmonary and aortic semilunar valves. Pressure generated by the left ventricle will be appreciably greater than the pressure generated by the right ventricle, since the existing pressure in the aorta will be so much higher. Nevertheless, both ventricles pump the same amount of blood. This quantity is referred to as stroke volume. Stroke volume will normally be in the range of 70–80 mL. Since ventricular systole began with an EDV of approximately 130 mL of blood, this means that there is still 50–60 mL of blood remaining in the ventricle following contraction. This volume of blood is known as the end systolic volume (ESV).

What term refers to a list of the elements that will replace the ones below them in single-replacement reactions?

Up series

growth series

probably series

activity series

Chemical reactivity trends are easy to predict when replacing anions in simple ionic compounds—simply use their relative positions on the periodic table. However, when replacing the cations, the trends are not as straightforward. This is partly because there are so many elements that can form cations; an element in one column on the periodic table may replace another element nearby, or it may not. A list called the activity series does the same thing the periodic table does for halogens: it lists the elements that will replace elements below them in single-replacement reactions. A simple activity series is shown below.

What cause many human diseases by killing host cells or disturbing their homeostasis?

bacteria

parasites

cancer

viruses

Viruses cause many human diseases by killing host cells or disturbing their homeostasis. Viruses are not affected by antibiotics. Several viral diseases can be treated with antiviral drugs or prevented with vaccines.

What two types of digestive systems do invertebrates have?

slow or complete

fast or slow

unstable or complete

incomplete or complete

Invertebrates have one of two types of digestive system: an incomplete or complete digestive system. Both are shown in Figure below . An incomplete digestive system consists of a digestive cavity with one opening. The single opening serves as both mouth and anus. A complete digestive system consists of a digestive tract with two openings. One opening is the mouth. The other is the anus.

What are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats?

arthropods

mammals

reptiles

amphibians

Amphibians are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats.

During exercise, the rate of blood returning to the heart does this?

reduces

remains stable

changes randomly

increases

Correlation Between Heart Rates and Cardiac Output Initially, physiological conditions that cause HR to increase also trigger an increase in SV. During exercise, the rate of blood returning to the heart increases. However as the HR rises, there is less time spent in diastole and consequently less time for the ventricles to fill with blood. Even though there is less filling time, SV will initially remain high. However, as HR continues to increase, SV gradually decreases due to decreased filling time. CO will initially stabilize as the increasing HR compensates for the decreasing SV, but at very high rates, CO will eventually decrease as increasing rates are no longer able to compensate for the decreasing SV. Consider this phenomenon in a healthy young individual. Initially, as HR increases from resting to approximately 120 bpm, CO will rise. As HR increases from 120 to 160 bpm, CO remains stable, since the increase in rate is offset by decreasing ventricular filling time and, consequently, SV. As HR continues to rise above 160 bpm, CO actually decreases as SV falls faster than HR increases. So although aerobic exercises are critical to maintain the health of the heart, individuals are cautioned to monitor their HR to ensure they stay within the target heart rate range of between 120 and 160 bpm, so CO is maintained. The target HR is loosely defined as the range in which both the heart and lungs receive the maximum benefit from the aerobic workout and is dependent upon age.

What is the pattern of spacing among individuals within the boundaries of the population?

equilibrium

frequency

diffusion

dispersion

null

What level is a feeding position in a food chain or web?

singular

neural

differentiation

trophic

Each food chain or food web has organisms at different trophic levels. A trophic level is a feeding position in a food chain or web. The trophic levels are identified in the food web in Figure above . All food chains and webs have at least two or three trophic levels, but they rarely have more than four trophic levels. The trophic levels are:.

What do most of the noble gas elements have in common?

four valence electrons

two valence electrons

zero valence electrons

eight valence electrons

Atoms can join together by forming a chemical bond, which is a very strong attraction between two atoms. Chemical bonds are formed when electrons in different atoms interact with each other to make an arrangement that is more stable than when the atoms are apart. What causes atoms to make a chemical bond with other atoms, rather than remaining as individual atoms? A clue comes by considering the noble gas elements, the rightmost column of the periodic table. These elements—helium, neon, argon, krypton, xenon, and radon—do not form compounds very easily, which suggests that they are especially stable as lone atoms. What else do the noble gas elements have in common? Except for helium, they all have eight valence electrons. Chemists have concluded that atoms are especially stable if they have eight electrons in their outermost shell. This useful rule of thumb is called the octet rule, and it is a key to understanding why compounds form.

What are the organisms that live in extreme conditions known as?

naturophiles

carotenoids

fibroblasts

extremophiles

Many archaeans are extremophiles. Extremophiles are organisms that live in extreme conditions. For example, some archaeans live around hydrothermal vents. A hydrothermal vent is a crack on the ocean floor. You can see one in Figure below . Boiling hot, highly acidic water pours out of the vent. These extreme conditions don't deter archaeans. They have evolved adaptations for coping with them. These conditions are like those on ancient Earth. This suggests that archaeans may have evolved very early in Earth's history.

Collision frequency is greater for what category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'?

contiguous

heterogeneous

analogous

homogeneous

Heterogeneous catalysts are easier to recover. Collision frequency is greater for homogeneous catalysts. Homogeneous catalysts are often more sensitive to temperature. Homogeneous catalysts are often more expensive. Saylor URL: http://www. saylor. org/books.

What does the pull of the moon's gravity on earth cause?

waves

earthquakes

storms

tides

Figure below shows why tides occur. The main cause of tides is the pull of the Moon’s gravity on Earth. The pull is greatest on whatever is closest to the Moon. Although the gravity pulls the land, only the water can move. As a result:.

A water molecule forms when oxygen (o) and _______ atoms react and are held together by covalent bonds?

steam

nitrogen

carbon

hydrogen (h)

An example of a chemical compound is water. A water molecule forms when oxygen (O) and hydrogen (H) atoms react and are held together by covalent bonds. Like other compounds, water always has the same chemical composition: a 2:1 ratio of hydrogen atoms to oxygen atoms. This is expressed in the chemical formula H 2 O. A model of a water molecule is shown in Figure below .

What force makes objects seem lighter in water?

gravity

resilient

surface tension

buoyant

Because of buoyant force, objects seem lighter in water. You may have noticed this when you went swimming and could easily pick up a friend or sibling under the water. Some of the person’s weight was countered by the buoyant force of the water.

What is the process by which the nucleus of a eukaryotic cell divides?

cytokinesis

meiosis

angiogenesis

mitosis

Mitosis is the process by which the nucleus of a eukaryotic cell divides. It happens in four phases: prophase, metaphase, anaphase, and telophase.

Iceland is made up of a series of?

earthquakes

glaciers

outcrops

volcanoes

A fissure eruption on a volcano in Iceland. The lava flows downhill and turns snow into steam. Iceland is made of a set of volcanoes that are the result of a hotspot that lies on a mid-ocean ridge. The island is the only location where the mid-ocean ridge can be seen above sea level. Icelandic volcanoes have made the news lately since some have shut down air traffic in parts of Europe.

What type of organism does not need oxygen for growth and dies in its presence?

symbiotic

acidic

aerobic

anaerobic

An anaerobic organism is any organism that does not need oxygen for growth and even dies in its presence. Obligate anaerobes will die when exposed to atmospheric levels of oxygen. Clostridium perfringens bacteria, which are commonly found in soil around the world, are obligate anaerobes. Infection of a wound by C. perfringens bacteria causes the disease gas gangrene. Obligate anaerobes use molecules other than oxygen as terminal electron acceptors.

What is the name of specialized organs that filter the lymph by percolation through a maze of connective tissue filled with white blood cells?

cochlea

alveoli

edema glands

lymph nodes

eventually diffuses back into the capillaries near the venules. The remaining 15% of blood plasma drains out from the interstitial fluid into nearby lymphatic vessels (Figure 40.18). The fluid in the lymph is similar in composition to the interstitial fluid. The lymph fluid passes through lymph nodes before it returns to the heart via the vena cava. Lymph nodes are specialized organs that filter the lymph by percolation through a maze of connective tissue filled with white blood cells. The white blood cells remove infectious agents, such as bacteria and viruses, to clean the lymph before it returns to the bloodstream. After it is cleaned, the lymph returns to the heart by the action of smooth muscle pumping, skeletal muscle action, and one-way valves joining the returning blood near the junction of the venae cavae entering the right atrium of the heart.

What are hydrocarbons most important use?

electricity

lightsource

food

fuel

Hydrocarbons have a wide variety of important uses, but their most important use is as fuels.

What protects tissues of the central nervous system from changes in ph?

sucrose ions

fatty ions

cerebrum

bicarbonate ions

Bicarbonate ions play an important role in neutralizing acids throughout the body. Bicarbonate ions are especially important for protecting tissues of the central nervous system from changes in pH. The central nervous system includes the brain, which is the body’s control center. If pH deviates too far from normal, the central nervous system cannot function properly. This can have a drastic effect on the rest of the body.

The air pressure is about 80% that of ________ pressure at sea level.

specific atmospheric

internal atmospheric

adverse atmospheric

standard atmospheric

The air pressure is about 80% that of standard atmospheric pressure at sea level. For significant figure purposes, the standard pressure of 760 mmHg has three significant figures.

Vertebrates - including fish, amphibians, reptiles, birds, and mammals - belong to what phylum?

animalia

angulata

nematota

chordata

Vertebrates are animals in Phylum Chordata. Modern vertebrates include fish, amphibians, reptiles, birds, and mammals. You can see examples of all these groups of vertebrates in Figure below .

In our wildflower population, the pool of what remains constant from one generation to the next?

genomes

DNA

eggs

genes

null

When a membrane uses energy to move a substance across it, what kind of transport is this?

inactive

fast

slow

active

x rms = 2Dt, where D is the diffusion constant, representative values of which are found in Table 12.2. • Osmosis is the transport of water through a semipermeable membrane from a region of high concentration to a region of low concentration. • Dialysis is the transport of any other molecule through a semipermeable membrane due to its concentration difference. • Both processes can be reversed by back pressure. • Active transport is a process in which a living membrane expends energy to move substances across it.

An electrostatic attraction between two ions that have exchanged what?

protons

neutrons

quasars

electrons

An electrostatic attraction between two ions that have exchanged electrons.

During what part of a person's development are they generally at their physical peak?

senility

late adulthood

infancy

early adulthood

Early adulthood starts at age 18 or 21. It continues until the mid-30s. During early adulthood, people are at their physical peak. They are also usually in good health. The ability to have children is greatest during early adulthood, as well. This is the stage of life when most people complete their education. They are likely to begin a career or take a full-time job. Many people also marry and start a family during early adulthood.

What type of movement involves sluggish segmentation, primarily in the transverse and descending colons?

accompanying contraction

gasutral contraction

photoreactive contraction

haustral contraction

Mechanical Digestion In the large intestine, mechanical digestion begins when chyme moves from the ileum into the cecum, an activity regulated by the ileocecal sphincter. Right after you eat, peristalsis in the ileum forces chyme into the cecum. When the cecum is distended with chyme, contractions of the ileocecal sphincter strengthen. Once chyme enters the cecum, colon movements begin. Mechanical digestion in the large intestine includes a combination of three types of movements. The presence of food residues in the colon stimulates a slow-moving haustral contraction. This type of movement involves sluggish segmentation, primarily in the transverse and descending colons. When a haustrum is distended with chyme, its muscle contracts, pushing the residue into the next haustrum. These contractions occur about every 30 minutes, and each last about 1 minute. These movements also mix the food residue, which helps the large intestine absorb water. The second type of movement is peristalsis, which, in the large intestine, is slower than in the more proximal portions of the alimentary canal. The third type is a mass movement. These strong waves start midway through the transverse colon and quickly force the contents toward the rectum. Mass movements usually occur three or four times per day, either while you eat or immediately afterward. Distension in the stomach and the breakdown products of digestion in the small intestine provoke the gastrocolic reflex, which increases motility, including mass movements, in the colon. Fiber in the diet both softens the stool and increases the power of colonic contractions, optimizing the activities of the colon.

Vertebrates evolved from primitive forms of which creature?

eukaryotes

gastropods

cephalopods

chordates

Vertebrates evolved from primitive chordates. This occurred about 550 million years ago. The earliest vertebrates may have been jawless fish, like the hagfish in Figure below . Vertebrates evolved a backbone to replace the notochord after the embryo stage. They also evolved a cranium, or bony skull, to enclose and protect the brain.

What does the aqueous fluid between the chloroplast membrane and the grana known as?

blood

plasma

water

stroma

Both chloroplasts and photosynthetic bacteria contain grana, neat stacks of flattened sac-shaped membrane compartments called thylakoids . Thylakoids can be considered a sub-organelle within the chloroplast. Between the chloroplast membrane and the grana is an aqueous fluid known as stroma . Thylakoids, especially the thylakoid membrane, organize patterns of proteins and other molecules which conduct photosynthesis, as shown in Figure below . In addition to enzymes, two basic types of molecules - pigments and electron carriers – are significant in this process. You can take a video tour of a chloroplast at Encyclopedia Britannica: Chloroplast : http://www. britannica. com/EBchecked/media/16440/Chloroplasts-circulate-within-plant-cells .

When a hypothesis is repeatedly confirmed, what can it then become?

evolution

Thesis

study

theory

When a hypothesis is confirmed repeatedly, it eventually becomes a theory – a general principle that is offered to explain natural phenomena. Note a key word – explanation. The theory offers a description of why something happens. A law, on the other hand, is a statement that is always true, but does not explain why. The law of gravity says a rock will fall when dropped, but does not explain why (gravitational theory is very complex and incomplete at present). The kinetic-molecular theory of gases, on the other hand, tells what happens when a gas is heated in a closed container (the pressure increases), but also explains why (the motions of the gas molecules are increased due to the change in temperature). Theories do not get “promoted” to laws because laws do not answer the “why” question.

Using a hammer to remove a nail changes both the direction and strength of the what?

static energy

kinetic energy

gravity

applied force

Using a hammer to remove a nail changes both the direction and strength of the applied force. Where is the fulcrum of the hammer when it is used in this way?.

Through which process are plants able to make their own food?

metabolism

cell division

glycolysis

photosynthesis

null

What kind of waves are sound waves?

spinning

External

internal

mechanical

A: It wouldn’t unless the vibrations were carried by another medium. Sound waves are mechanical waves, so they can travel only though matter and not through empty space.

The protein without the prosthetic group is known as the what?

spicule

xerophyte

monoprotein

apoprotein

As we will return to later, proteins are functional entities, composed of polypeptides and prosthetic group. The prosthetic group is essential for normal protein function. The protein without the prosthetic group is known as the apoprotein. biofundamentals – coreBIO.

What connections allow heterocysts to transport fixed nitrogen to neighboring cells and to receive carbohydrates?

peptide

neurons

heterogeneity

intercellular

null

The classes anthozoa, scyphozoa, cubozoa, and hydrozoa make up what phylum?

poriferia

crinoids

mollusca

cnidaria

differentiated cell types in each tissue layer, such as nerve cells, enzyme-secreting cells, and nutrient-absorbing cells, as well as intercellular connections between the cells. However, organs and organ systems are not present in this phylum. The nervous system is primitive, with nerve cells scattered across the body in a network. The function of the nerve cells is to carry signals from sensory cells and to contractile cells. Groups of cells in the nerve net form nerve cords that may be essential for more rapid transmission. Cnidarians perform extracellular digestion, with digestion completed by intracellular digestive processes. Food is taken into the gastrovascular cavity, enzymes are secreted into the cavity, and the cells lining the cavity absorb the nutrient products of the extracellular digestive process. The gastrovascular cavity has only one opening that serves as both a mouth and an anus (an incomplete digestive system). Like the sponges, Cnidarian cells exchange oxygen, carbon dioxide, and nitrogenous wastes by diffusion between cells in the epidermis and gastrodermis with water. Cnidarian Diversity The phylum Cnidaria contains about 10,000 described species divided into four classes: Anthozoa, Scyphozoa, Cubozoa, and Hydrozoa. The class Anthozoa includes all cnidarians that exhibit a sessile polyp body plan only; in other words, there is no medusa stage within their life cycle. Examples include sea anemones, sea pens, and corals, with an estimated number of 6,100 described species. Sea anemones are usually brightly colored and can attain a size of 1.8 to 10 cm in diameter. These animals are usually cylindrical in shape and are attached to a substrate. A mouth opening is surrounded by tentacles bearing cnidocytes (Figure 15.12).

Where does waste enter the large intestine from?

liver

the small tissue

kidneys

the small intestine

The large intestine is a wide tube that connects the small intestine with the anus. In adults, it is about five feet long. Waste enters the large intestine from the small intestine in a liquid state. As the waste moves through the large intestine, excess water is absorbed from it. After the excess water is absorbed, the remaining solid waste is called feces.

What do different soil horizons show different amounts of?

evolution

distortion

secretion

alteration

Soil horizons are layers within a soil. Different soil horizons show different amounts of alteration.

What is the main source of energy for your body?

fats

proteins

vitamins

carbohydrates

Carbohydrates, proteins, and lipids are categories of organic compounds. They give your body energy, though carbohydrates are the main source of energy. Proteins provide building materials, such as amino acids to build your own proteins. Proteins, vitamins, and minerals also help control body processes. Carbohydrates include sugars such as the glucose made by photosynthesis. Often glucose is stored in large molecules such as starch. Proteins are found in foods like meats and nuts. Lipids includes fats and oils. Though you should stay away from many types of fats, others are needed by your body. Important vitamins include vitamins A, B (multiple types) C, D, and E. Important minerals include calcium and potassium. What should you drink to get calcium? Milk is a good source.

What are thin, very small tail-like projections that extend outward from the cell body that allow protists to move?

fins

antennae

notochords

cilia

The ciliates are protists that move by using cilia. Cilia are thin, very small tail-like projections that extend outward from the cell body. Cilia beat back and forth, moving the protist along. Paramecium has cilia that propel it.

Earthquakes, which may occur on california’s abundant faults, can also trigger what?

floods

Waves

avalanches

landslides

Some communities have developed landslide warning systems. Around San Francisco Bay, the National Weather Service and the U. S. Geological Survey use rain gauges to monitor soil moisture. If soil becomes saturated, the weather service issues a warning. Earthquakes, which may occur on California’s abundant faults, can also trigger landslides.

In which way do particles of water move in deep water?

ellipses

currents

parabolas

circles

In deep water, particles of water just move in circles. They don’t actually move closer to shore with the energy of the waves. However, near the shore where the water is shallow, the waves behave differently. They start to drag on the bottom, creating friction (see Figure below ). The friction slows down the bottoms of the waves, while the tops of the waves keep moving at the same speed. This causes the waves to get steeper until they topple over and crash on the shore. The crashing waves carry water onto the shore as surf.

What is the name of the study of heat engines?

Chemical dynamics

chemistry

biology

thermodynamics

Thermodynamics is the study of heat engines. Any engine or power plant obeys the laws of thermodynamics. The first law of thermodynamics is a statement of conservation of energy. Total energy, including heat, is conserved in any process and in the complete cycle of a heat engine. The second law of thermodynamics as it applies to heat engines gives an absolute limit on the efficiency of any heat engine that goes through repetitious cycles.

Mechanical waves can only trave through what?

water

light

air

matter

The energy of a mechanical wave can travel only through matter. The matter through which the wave travels is called the medium ( plural , media). The medium in the water wave pictured above is water, a liquid. But the medium of a mechanical wave can be any state of matter, even a solid.

If you examine eyeglasses for nearsighted people, you will find the lenses are thinnest in the center and of what shape?

square

convex

asymmetrical

concave

Discussion The negative power indicates a diverging (or concave) lens, as expected. The spectacle produces a case 3 image closer to the eye, where the person can see it. If you examine eyeglasses for nearsighted people, you will find the lenses are thinnest in the center. Additionally, if you examine a prescription for eyeglasses for nearsighted people, you will find that the prescribed power is negative and given in units of diopters.

What do you call air flowing over earth’s surface?

air pressure

gas

steam

wind

Air always flows from an area of higher pressure to an area of lower pressure. Air flowing over Earth’s surface is called wind . The greater the difference in pressure, the stronger the wind blows.

What three particles make up most atoms?

neutrons, protons and radii

protons, electrons and nucleus

micrometres , electrons and neutrons

protons, electrons and neutrons

A neutron is one of three main particles that make up the atom. The other two particles are the proton and electron. Atoms of all elements—except for most atoms of hydrogen—have neutrons in their nucleus. The nucleus is the small, dense region at the center of an atom where protons are also found. Atoms generally have about the same number of neutrons as protons. For example, all carbon atoms have six protons and most also have six neutrons. A model of a carbon atom is shown in the Figure below . For an excellent video explaining the structure of atoms, including neutrons, go to this URL:.

How can one dimensional vectors be added?

exponentially

incrementally

sequentially

arithmetically

Vectors that are in one dimension can be added arithmetically.

What is caused by the reaction of nonmetal oxides with water in the atmosphere?

yellow rain

ozone rain

carbon rain

acid rain

Acid rain is caused by the reaction of nonmetal oxides with water in the atmosphere. One such reaction involves nitrogen dioxide (NO2) and produces nitric acid (HNO3): 3NO2 + H2O → 2HNO3 + NO If 1.82 × 1013 g of NO2 enter the atmosphere every year due to human activities, potentially how many grams of HNO3 can be produced annually?.

Into how many basic regions can the aquatic biome be broken down?

five

six

One

two

null

The top of the saturated rock layer is called what?

calcified layer

sand layer

compressed layer

water table

The top of the saturated rock layer above ( Figure above ) is called the water table . The water table isn’t like a real table. It doesn’t remain firmly in one place. Instead, it rises or falls, depending on how much water seeps down from the surface. The water table is higher when there is a lot of rain, and it is lower when the weather is dry.

Which field studies how to tailor medical treatments to our genetic profiles?

proteomics

immunology

metagenomics

pharmacogenomics

We know that, thanks to our DNA, each of us is a little bit different. Some of those differences are obvious, like eye and hair color. Others are not so obvious, like how our bodies react to medication. Researchers are beginning to look at how to tailor medical treatments to our genetic profiles, in a relatively new field called pharmacogenomics . Some of the biggest breakthroughs have been in cancer treatment. For additional information on this “personalized medicine,” listen to http://www. kqed. org/quest/radio/personalized-medicine and see http://www. kqed. org/quest/blog/2009/09/11/reporters-notes-personalized-medicine/ .

Research that focuses on understanding basic properties and processes without concern for the usefulness of this understanding is known as what kind of research?

focused research

disconnected research

applied research

pure research

Pure research focuses on understanding basic properties and processes.

Cells of what category of organisms can be organized at the level of cells, tissues, organs, and organ systems?

complex

biomolecular

intricate

multicellular

Cells can exist independently as single-celled organisms or with other cells as multicellular organisms. Cells of a multicellular organism can be organized at the level of cells, tissues, organs, and organ systems.

What property of materials describes the ease in which they can be molded into thin sheets?

rigidity

plasticity

permeability

malleability

A physical property is a characteristic of a substance that can be observed or measured without changing the identity of the substance. Silver is a shiny metal that conducts electricity very well. It can be molded into thin sheets, a property called malleability. Salt is dull and brittle and conducts electricity when it has been dissolved into water, which it does quite easily. Physical properties of matter include color, hardness, malleability, solubility, electrical conductivity, density, melting points , and boiling points .

What do you call materials that have low resistance to electric current?

good insulator

electromagnets

poor conductors

electric conductors

Materials that have low resistance to electric current are called electric conductors . Many metals—including copper, aluminum, and steel—are good conductors of electricity. The outer electrons of metal atoms are loosely bound and free to move, allowing electric current to flow. Water that has even a tiny amount of impurities is an electric conductor as well.

What is the term for the transfer of heat by a current?

diffusion

conduction

radiation

convection

Convection is the transfer of heat by a current. Convection happens in a liquid or a gas. Air near the ground is warmed by heat radiating from Earth's surface. The warm air is less dense, so it rises. As it rises, it cools. The cool air is dense, so it sinks to the surface. This creates a convection current ( Figure below ). Convection is the most important way that heat travels in the atmosphere.

Arterioles receive blood from arteries, which are vessels with a much larger lumen. as their own lumen averages just 30 micrometers or less, arterioles are critical in slowing down—or resisting—blood flow. the arterioles can also constrict or dilate, which varies their what?

advantage

osmosis

gravity

resistance

Chapter 20 1 Water. 3 A 5 C 7 C 9 A 11 D 13 B 15 A 17 C 19 A 21 C 23 D 25 D 27 C 28 Arterioles receive blood from arteries, which are vessels with a much larger lumen. As their own lumen averages just 30 micrometers or less, arterioles are critical in slowing down—or resisting—blood flow. The arterioles can also constrict or dilate, which varies their resistance, to help distribute blood flow to the tissues. 30 This is a venule. 32 People who stand upright all day and are inactive overall have very little skeletal muscle activity in the legs. Pooling of blood in the legs and feet is common. Venous return to the heart is reduced, a condition that in turn reduces cardiac output and therefore oxygenation of tissues throughout the body. This could at least partially account for the patient’s fatigue and shortness of breath, as well as her “spaced out” feeling, which commonly reflects reduced oxygen to the brain. 34 False. The plasma proteins suspended in blood cannot cross the semipermeable capillary cell membrane, and so they remain in the plasma within the vessel, where they account for the blood colloid osmotic pressure. 36 Nitric oxide is a very powerful local vasodilator that is important in the autoregulation of tissue perfusion. If it were not broken down very quickly after its release, blood flow to the region could exceed metabolic needs. 38 The gonadal veins drain the testes in males and the ovaries in females. 40 Angiogenesis inhibitors are drugs that inhibit the growth of new blood vessels. They can impede the growth of tumors by limiting their blood supply and therefore their access to gas and nutrient exchange.

What is the circular center of a hurricane better known as?

the focus

the epicenter

the nose

the eye

At the center of a hurricane is a small area where the air is calm and clear. This is called the eye of the hurricane ( Figure below ). The eye forms at the low-pressure center of the hurricane. Air in the eye rises upward.

Are most glaciers currently growing or shrinking?

no change

growing

freezing

shrinking

Glaciers are not static; they grow, they move and they shrink. Currently, most glaciers are shrinking.

What kind of model - which includes producers, consumers and decomposers - shows the interactions between organisms across trophic levels?

organic web

interdepence web

fuel web

food web

Figure 20.6 This food web shows the interactions between organisms across trophic levels. Arrows point from an organism that is consumed to the organism that consumes it. All the producers and consumers eventually become nourishment for the decomposers (fungi, mold, earthworms, and bacteria in the soil). (credit "fox": modification of work by Kevin Bacher, NPS; credit "owl": modification of work by John and Karen Hollingsworth, USFWS; credit "snake": modification of work by Steve Jurvetson; credit "robin": modification of work by Alan Vernon; credit "frog": modification of work by Alessandro Catenazzi; credit "spider": modification of work by "Sanba38"/Wikimedia Commons; credit "centipede": modification of work by “Bauerph”/Wikimedia Commons; credit "squirrel": modification of work by Dawn Huczek; credit "mouse": modification of work by NIGMS, NIH; credit "sparrow": modification of work by David Friel; credit "beetle": modification of work by Scott Bauer, USDA Agricultural Research Service; credit "mushrooms": modification of work by Chris Wee; credit "mold": modification of work by Dr. Lucille Georg, CDC; credit "earthworm": modification of work by Rob Hille; credit "bacteria": modification of work by Don Stalons, CDC).

The multifidus muscle of the lumbar region helps extend and laterally flex this?

knee

forearm

pelvic muscle

vertebal column

are associated. The semispinalis muscles include the semispinalis capitis, the semispinalis cervicis, and the semispinalis thoracis. The multifidus muscle of the lumbar region helps extend and laterally flex the vertebral column. Important in the stabilization of the vertebral column is the segmental muscle group, which includes the interspinales and intertransversarii muscles. These muscles bring together the spinous and transverse processes of each consecutive vertebra. Finally, the scalene muscles work together to flex, laterally flex, and rotate the head. They also contribute to deep inhalation. The scalene muscles include the anterior scalene muscle (anterior to the middle scalene), the middle scalene muscle (the longest, intermediate between the anterior and posterior scalenes), and the posterior scalene muscle (the smallest, posterior to the middle scalene).

What does k stand for on the periodic table?

calcium

aluminum

magnesium

potassium

Q: The table shown in the Figure above is called the periodic table of the elements. Each symbol stands for a different element. What do you think the symbol K stands for?.

Beta decay occurs when a nucleus has too few of what relative to protons?

nuclei

protons

electrons

neutrons

Beta decay occurs when a nucleus is unstable because it has too many or too few neutrons relative to protons. The nucleus emits a beta particle and energy. A beta particle is either an electron (beta-minus decay) or a positron (beta-plus decay).

Trees have woody stems covered with what?

shells

larvae

rust

bark

Trees have woody stems covered with bark.

What prevents an object from moving in a straight line at a constant speed?

matter

weight

friction

force

Newton’s first law implies that an object oscillating back and forth is experiencing forces. Without force, the object would move in a straight line at a constant speed rather than oscillate. Consider, for example, plucking a plastic ruler to the left as shown in Figure 16.2. The deformation of the ruler creates a force in the opposite direction, known as a restoring force. Once released, the restoring force causes the ruler to move back toward its stable equilibrium position, where the net force on it is zero. However, by the time the ruler gets there, it gains momentum and continues to move to the right, producing the opposite deformation. It is then forced to the left, back through equilibrium, and the process is repeated until dissipative forces dampen the motion. These forces remove mechanical energy from the system, gradually reducing the motion until the ruler comes to rest. The simplest oscillations occur when the restoring force is directly proportional to displacement. When stress and strain were covered in Newton’s Third Law of Motion, the name was given to this relationship between force and displacement was Hooke’s law:.

The effect of acetylcholine in heart muscle is inhibitory rather than what?

exofactory

neurotransmitter

olfactory

excitatory

null

What is the division of the cytoplasm in eukaryotic cells?

metamorphosis

electrolysis

andronisis

cytokinesis

The second major step is cytokinesis . As in prokaryotic cells, the cytoplasm must divide. Cytokinesis is the division of the cytoplasm in eukaryotic cells, resulting in two genetically identical daughter cells.

The white of an egg becomes opaque when cooked because what are insoluble and solidify?

fatty acids

acetic proteins

calcium molecules

denatured proteins

null

What kind of plants lack xylem or phloem to transport nutrients, water, and food?

spicule

single-celled

trichina

nonvascular

Nonvascular plants evolved first. They are distinct from the algae because they keep the embryo inside of the reproductive structure after fertilization. These plants do not have vascular tissue, xylem or phloem, to transport nutrients, water, and food. Examples include mosses, liverworts, and hornworts. Without vascular tissue, these plants do not grow very tall.

Exemplified by baring teeth, what type of displays are common in the animal kingdom, and sometimes serve as a 'bluff'?

sexual

passive

defensive

aggressive

incorrectly or a proper response is not given, the mating ritual is abandoned and the mating attempt will be unsuccessful. The mating display of the common stork is shown in Figure 45.37. Aggressive displays are also common in the animal kingdom. An example is when a dog bares its teeth when it wants another dog to back down. Presumably, these displays communicate not only the willingness of the animal to fight, but also its fighting ability. Although these displays do signal aggression on the part of the sender, it is thought that these displays are actually a mechanism to reduce the amount of actual fighting that occurs between members of the same species: they allow individuals to assess the fighting ability of their opponent and thus decide whether it is “worth the fight. ” The testing of certain hypotheses using game theory has led to the conclusion that some of these displays may overstate an animal’s actual fighting ability and are used to “bluff” the opponent. This type of interaction, even if “dishonest,” would be favored by natural selection if it is successful more times than not.

The preferred phase a substance adopts can change with temperature. at low temperatures, most substances are solids (only helium is predicted to be a liquid at absolute zero). as the temperature increases, those substances with very weak intermolecular forces become gases directly in a process called this?

Freezing Point

speciation

vaporization

sublimation

The preferred phase a substance adopts can change with temperature. At low temperatures, most substances are solids (only helium is predicted to be a liquid at absolute zero). As the temperature increases, those substances with very weak intermolecular forces become gases directly (in a process called sublimation, which will be discussed in Section 10.2 "Phase Transitions: Melting, Boiling, and Subliming"). Substances with weak interactions can become liquids as the temperature increases. As the temperature increases even more, the individual particles will have so much energy that the intermolecular forces are overcome, so the particles separate from each other, and the substance becomes a gas (assuming that their chemical bonds are not so weak that the compound decomposes from the high temperature). Although is it difficult to predict the temperature ranges for which solid, liquid, or gas is the preferred phase for any random substance, all substances progress from solid to liquid to gas in that order as temperature increases.

What pigment do slow fibers contain?

iron

melolin

hemoglobin

myoglobin

Which of the following statements is true? a. Fast fibers have a small diameter. Fast fibers contain loosely packed myofibrils. Fast fibers have large glycogen reserves. Fast fibers have many mitochondria. Which of the following statements is false? a. Slow fibers have a small network of capillaries. Slow fibers contain the pigment myoglobin. Slow fibers contain a large number of mitochondria. Slow fibers contract for extended periods. Cardiac muscles differ from skeletal muscles in that they ________. are striated b. utilize aerobic metabolism.

What are clathrin, copi and copii types of?

artery coats

replication coats

pathogen coats

vesicle coats

The vesicle coat selects specific proteins as cargo. It selects cargo proteins by binding to sorting signals. These complexes cluster in the membrane, forming a vesicle buds, or coated pit . There are three types of vesicle coats: clathrin , COPI and COPII. Clathrin coats are found on vesicles trafficking between the Golgi and plasma membrane, the Golgi and endosomes, and the plasma membrane and endosomes. COPI ( coat protein complex) coated vesicles are responsible for transport from the cis -Golgi to the ER (retrograde transport), while COPII coated vesicles are responsible for transport from the ER to the Golgi (anterograde transport). Low-density lipoprotein (LDL) receptors aggregate in clathrin coated pits prior to internalization.

What is the name for the force that attracts water molecules to other polar substances?

aeration

osmosis

diffusion

adhesion

null

All alkaline earth metals have similar properties because they all have two what?

caesium electrons

balanced electrons

transitions electrons

valence electrons

All alkaline Earth metals have similar properties because they all have two valence electrons. They readily give up their two valence electrons to achieve a full outer energy level, which is the most stable arrangement of electrons. As a result, they are very reactive, although not quite as reactive as the alkali metals in group 1. For example, alkaline Earth metals will react with cold water, but not explosively as alkali metals do. Because of their reactivity, alkaline Earth metals never exist as pure substances in nature. Instead, they are always found combined with other elements.

A solenoid or coil wrapped around iron or certain other metals can form what kind of magnet?

polarized magnet

permanent magnet

superconductor

electromagnet

An electromagnet is a solenoid wrapped around a bar of iron or other ferromagnetic material. The magnetic field of the solenoid magnetizes the iron bar.

Is the yolk more or less concentrated toward the animal pole?

no change

more concentrated

same concentrated

less concentrated

null

What are the location where bones come together?

fingers

muscles

Knees

joints

The adult human body has 206 bones, and with the exception of the hyoid bone in the neck, each bone is connected to at least one other bone. Joints are the location where bones come together. Many joints allow for movement between the bones. At these joints, the articulating surfaces of the adjacent bones can move smoothly against each other. However, the bones of other joints may be joined to each other by connective tissue or cartilage. These joints are designed for stability and provide for little or no movement. Importantly, joint stability and movement are related to each other. This means that stable joints allow for little or no mobility between the adjacent bones. Conversely, joints that provide the most movement.

What term denotes lower levels of exposure, for instance to radiation, over a longer period of time?

excess exposure

non-exposure

recent exposure

chronic exposure

Exposure gives an indication of the amount of radiation that travels through the air. Two factors influence the amount of exposure a person may receive – time and intensity. Acute exposure indicates a large amount of radiation received over a short period of time. Chronic exposure deals with lower levels of exposure over a longer period of time. Dose equivalence combines the amount of radiation received and the medical effect of that radiation. Calculations of exposure and dose equivalence are complicated and will not be pursued at this time.

What causes water molecules to stay close to each other?

friction

oxidation

surface tension

hydrogen bonding

null

What is the main cause of recent global warming?

insect overpopulation

ice ages

solar flares

human beings

Natural processes caused earlier climate changes. Human beings are the main cause of recent global warming.

In solids, particles can't overcome the force of attraction between them because they lack what?

momentum

gravity

residual energy

kinetic energy

In solids, particles don’t have enough kinetic energy to overcome the force of attraction between them. The particles are packed closely together and cannot move around. All they can do is vibrate. This explains why solids have a fixed volume and shape.

What are the organelles where the process of photosynthesis takes place in plants and algae.

ribosomes

fibroblasts

mitochondria

chloroplasts

Chloroplasts are the organelles where the process of photosynthesis takes place in plants and algae.

What process occurs when two alleles are expressed equally in the phenotype of the heterozygote?

codependence

pollenation

fertilization

codominance

Codominance occurs when both alleles are expressed equally in the phenotype of the heterozygote. The red and white flower in the figure has codominant alleles for red petals and white petals.

Magnetic poles always occur in pairs - what are the names of each pole?

southwest and south

prime and equator

tropic and arctic

north and south

• Like poles repel and unlike poles attract. • Magnetic poles always occur in pairs of north and south—it is not possible to isolate north and south poles.

Anemia is a disease that affects what?

kidney

brain

heart

blood

Red meat, legumes, and spinach are all good sources of iron. Getting enough iron in your diet is important to prevent anemia. Anemia is a blood disease that causes you to feel weak and tired. Although anemia is caused by a nutrient deficiency, other blood diseases are genetic diseases, or forms of cancer.

The end of a pine tree branch bears the male cones that produce what?

needles

spores

flowers

pollen

The end of a pine tree branch bears the male cones that produce the pollen.

What is the material inside the cell membrane called?

chloroplasm

mucus

cerebellum

cytoplasm

Cytoplasm is the material inside the cell membrane. It includes a watery substance called cytosol. Besides water, cytosol contains enzymes and other substances. Cytoplasm also includes other cell structures suspended in the cytosol.

The energy stored in the organic molecules of food ultimately comes from where?

plant

earth

ocean

sun

null

Sulfur dioxide produced by burning coal is the leading cause of what deadly phenomenon?

dioxide rain

hail

carbon rain

acid rain

Another problem with coal is that most coal contains sulfur. As it burns, the sulfur goes into the air as sulfur dioxide. Sulfur dioxide is the main cause of acid rain. Acid rain can be deadly to plants, animals, and whole ecosystems. Burning coal also puts a large number of small solid particulates into the air. These particles are dangerous to people, especially those who have asthma. People with asthma may end up in the hospital on days when particulate pollution is high.

When an eagle, a land eater, goes and gets fish from the sea, as well, its called?

descending food web

overlapping food source

food chain mixing

overlapping food web

Food webs also overlap. For example, an eagle is part of a land food web. But it might go to the sea to grab a fish. That fish is part of a marine food web.

Where the axon emerges from the cell body, there is a special region referred to as the what?

cellular hillock

axosomatic synapse

dendrite

axon hillock

Where the axon emerges from the cell body, there is a special region referred to as the axon hillock. This is a tapering of the cell body toward the axon fiber. Within the axon hillock, the cytoplasm changes to a solution of limited components called axoplasm. Because the axon hillock represents the beginning of the axon, it is also referred to as the initial segment. Many axons are wrapped by an insulating substance called myelin, which is actually made from glial cells. Myelin acts as insulation much like the plastic or rubber that is used to insulate electrical wires. A key difference between myelin and the insulation on a wire is that there are gaps in the myelin covering of an axon. Each gap is called a node of Ranvier and is important to the way that electrical signals travel down the axon. The length of the axon between each gap, which is wrapped in myelin, is referred to as an axon segment. At the end of the axon is the axon terminal, where there are usually several branches extending toward the target cell, each of which ends in an enlargement called a synaptic end bulb. These bulbs are what make the connection with the target cell at the synapse.

The specialized study of the motion of objects that are atomic/subatomic in size is called what?

enthalpy

string theory

atomic mechanics

quantum mechanics

The study of motion of large objects such as baseballs is called mechanics, or more specifically classical mechanics. Because the quantum nature of the electron and other tiny particles moving at high speeds, classical mechanics is inadequate to accurately describe their motion. Quantum mechanics is the study of the motion of objects that are atomic or subatomic in size and thus demonstrate wave-particle duality. In classical mechanics, the size and mass of the objects involved effectively obscures any quantum effects so that such objects appear to gain or lose energies in any amounts. Particles whose motion is described by quantum mechanics gain or lose energy in the small pieces called quanta .