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What is the term for the process in which an area that has never before been colonized changes through time? | colony succession | global air currents | membranes | ecological succession | Ecological succession is the process in which a community changes through time. Primary succession occurs in an area that has never before been colonized. Secondary succession occurs in a formerly inhabited area that was disturbed. | geography |
All the major landmasses moved together to form one supercontinent in which period? | Cenozoic | symbiosis | solar activity | permian | During the Permian Period, all the major landmasses moved together to form one supercontinent. The supercontinent has been named Pangaea. You can see how it looked in Figure below . At this time, temperatures were extreme and the climate became very dry. As a result, plants and animals evolved ways to cope with dryness. For example, reptiles evolved leathery skin. This helped prevent water loss. Plants evolved waxy leaves for the same purpose. | geography |
A problem with using food chains to describe ecosystems is that some organisms can feed on or be consumed by species from more than one of what level? | pH level | biome level | habitat level | trophic level | There is a one problem when using food chains to accurately describe most ecosystems. Even when all organisms are grouped into appropriate trophic levels, some of these organisms can feed on species from more than one trophic level; likewise, some of these organisms can be eaten by species from multiple trophic levels. In other words, the linear model of ecosystems, the food chain, is not completely descriptive of ecosystem structure. A holistic model—which accounts for all the interactions between different species and their complex interconnected relationships with each other and with the environment—is a more accurate and descriptive model for ecosystems. A food web is a graphic representation of a holistic, non-linear web of primary producers, primary consumers, and higher-level consumers used to describe ecosystem structure and dynamics (Figure 46.6). | biology |
What is the practical application of scientific principles and discoveries to develop things that make our lives easier? | inside nuclei | Movement | Caelum | engineering | Engineering is the practical application of scientific principles and discoveries to develop things that make our lives easier. Is medicine science or engineering? Justify your answer. | physics |
In plants, a cell plate is formed during cell cytokinesis by golgi vesicles fusing at the what? | schizonts | characteristic | gender-linked traits | metaphase plate | Telophase I and Cytokinesis In telophase, the separated chromosomes arrive at opposite poles. The remainder of the typical telophase events may or may not occur, depending on the species. In some organisms, the chromosomes decondense and nuclear envelopes form around the chromatids in telophase I. In other organisms, cytokinesis—the physical separation of the cytoplasmic components into two daughter cells—occurs without reformation of the nuclei. In nearly all species of animals and some fungi, cytokinesis separates the cell contents via a cleavage furrow (constriction of the actin ring that leads to cytoplasmic division). In plants, a cell plate is formed during cell cytokinesis by Golgi vesicles fusing at the metaphase plate. This cell plate will ultimately lead to the formation of cell walls that separate the two daughter cells. Two haploid cells are the end result of the first meiotic division. The cells are haploid because at each pole, there is just one of each pair of the homologous chromosomes. Therefore, only one full set of the chromosomes is present. This is why the cells are considered haploid—there is only one chromosome set, even though each homolog still consists of two sister chromatids. Recall that sister chromatids are merely duplicates of one of the two homologous chromosomes (except for changes that occurred during crossing over). In meiosis II, these two sister chromatids will separate, creating four haploid daughter cells. | biology |
What is the type of volcano with a tall cone shape that you picture when picturing a volcano? | inactive | advanced | active | composite | A composite volcano forms the tall cone shape you usually think of when you think of a volcano. Shield volcanoes are huge, gently sloping volcanoes. Cinder cones are small, cone-shaped volcanoes. | geography |
The amount of what entering the eyes helps control the biological clock? | digestion system | in the veins | transition | light | In many species, including humans, circadian rhythms are controlled by a tiny structure called the biological clock . This structure is located in a gland at the base of the brain. The biological clock sends signals to the body. The signals cause regular changes in behavior and body processes. The amount of light entering the eyes helps control the biological clock. The clock causes changes that repeat every 24 hours. | biology |
Protists are classified as animal-like, plant-like, or what else? | harden | chronic | transportation | fungus-like | Protists are classified as animal-like, plant-like, or fungus-like. The three groups differ mainly in how they obtain carbon and energy. | biology |
Satellite and schwann cells are the two types of what kind of cell found in the pns? | their color | dendritic | glial cells | glial | Glial Cells of the PNS One of the two types of glial cells found in the PNS is the satellite cell. Satellite cells are found in sensory and autonomic ganglia, where they surround the cell bodies of neurons. This accounts for the name, based on their appearance under the microscope. They provide support, performing similar functions in the periphery as astrocytes do in the CNS—except, of course, for establishing the BBB. The second type of glial cell is the Schwann cell, which insulate axons with myelin in the periphery. Schwann cells are different than oligodendrocytes, in that a Schwann cell wraps around a portion of only one axon segment and no others. Oligodendrocytes have processes that reach out to multiple axon segments, whereas the entire Schwann cell surrounds just one axon segment. The nucleus and cytoplasm of the Schwann cell are on the edge of the myelin sheath. The relationship of these two types of glial cells to ganglia and nerves in the PNS is seen in Figure 12.12. | biology |
What compound has positive and negative ions? | carbon reaction | organic compound | protein | ionic | Ionic compounds have positive ions and negative ions. | chemistry |
What can be calculated given the mass and speed of an object? | m. Type | preduction | protonation | kinetic energy | Given the mass and speed of an object, calculate its kinetic energy. | physics |
Earthquakes mark the motions of colliding plates and the locations where plates plunge into what? | the core | the mesosphere | the crust | the mantle | Convergent plate boundaries also produce strong, deadly earthquakes. Earthquakes mark the motions of colliding plates and the locations where plates plunge into the mantle. These earthquakes can be shallow, intermediate or deep focus. | geography |
The ambrosia beetle bores holes in? | leaves | flowers | dirt | tree bark | Ambrosia beetles bore holes in tree bark and “plant” fungal spores in the holes. The holes in the bark give the fungi an ideal place to grow. The beetles harvest fungi from their “garden. ”. | biology |
What effect, related to weather forecasting, occurs not only for sound but for any wave when there is relative motion between the observer and the source? | precipitation | pulse | echo | doppler | Mole-mole calculations are not the only type of calculations that can be performed using balanced chemical equations. Recall that the molar mass can be determined from a chemical formula and used as a conversion factor. We can add that conversion factor as another step in a calculation to make a molemass calculation, where we start with a given number of moles of a substance and calculate the mass of another substance involved in the chemical equation, or vice versa. For example, suppose we have the balanced chemical equation. | physics |
What is the science of how traits are passed from parents to offspring? | hydrosphere | bacteria and tumors | cross matching | heredity | science of heredity, or how traits are passed from parents to offspring. | biology |
When an electron transitions from an excited state to a less excited state, or ground state, the difference in energy is emitted as a what? | in cold climates | electric potential | pelvis | photon | which is identical to the Rydberg equation for R ∞ = k . When Bohr calculated his theoretical value for the hc Rydberg constant, R ∞, and compared it with the experimentally accepted value, he got excellent agreement. Since the Rydberg constant was one of the most precisely measured constants at that time, this level of agreement was astonishing and meant that Bohr’s model was taken seriously, despite the many assumptions that Bohr needed to derive it. The lowest few energy levels are shown in Figure 6.14. One of the fundamental laws of physics is that matter is most stable with the lowest possible energy. Thus, the electron in a hydrogen atom usually moves in the n = 1 orbit, the orbit in which it has the lowest energy. When the electron is in this lowest energy orbit, the atom is said to be in its ground electronic state (or simply ground state). If the atom receives energy from an outside source, it is possible for the electron to move to an orbit with a higher n value and the atom is now in an excited electronic state (or simply an excited state) with a higher energy. When an electron transitions from an excited state (higher energy orbit) to a less excited state, or ground state, the difference in energy is emitted as a photon. Similarly, if a photon is absorbed by an atom, the energy of the photon moves an electron from a lower energy orbit up to a more excited one. We can relate the energy of electrons in atoms to what we learned previously about energy. The law of conservation of energy says that we can neither create nor destroy energy. Thus, if a certain amount of external energy is required to excite an electron from one energy level to another, that same amount of energy will be liberated when the electron returns to its initial state (Figure 6.15). In effect, an atom can “store” energy by using it to promote an electron to a state with a higher energy and release it when the electron returns to a lower state. The energy can be released as one quantum of energy, as the electron returns to its ground state (say, from n = 5 to n = 1), or it can be released as two or more smaller quanta as the electron falls to an intermediate state, then to the ground state (say, from n = 5 to n = 4, emitting one quantum, then to n = 1, emitting a second quantum). Since Bohr’s model involved only a single electron, it could also be applied to the single electron ions He+, Li2+, Be3+, and so forth, which differ from hydrogen only in their nuclear charges, and so one-electron atoms and ions are collectively referred to as hydrogen-like atoms. The energy expression for hydrogen-like atoms is a generalization of the hydrogen atom energy, in which Z is the nuclear charge (+1 for hydrogen, +2 for He, +3 for Li, and so on) and k has a value of 2.179 × 10–18 J. E n = − kZ2 n. | physics |
Water from the land and oceans enters the atmosphere by which process? | species populations | divergent speciation | coriolis effect | evaporation | Figure 46.14 Water from the land and oceans enters the atmosphere by evaporation or sublimation, where it condenses into clouds and falls as rain or snow. Precipitated water may enter freshwater bodies or infiltrate the soil. The cycle is complete when surface or groundwater reenters the ocean. (credit: modification of work by John M. Evans and Howard Perlman, USGS). | geography |
What country put seven salyut space stations into orbit between 1971 and 1982? | acid pairs | United States | newtonian motion | soviet union | Between 1971 and 1982, the Soviets put a total of seven Salyut space stations into orbit. Figure below shows the last of these, Salyut 7. These were all temporary stations. They were launched and later inhabited by a human crew. Three of the Salyut stations were used for secret military purposes. The others were used to study the problems of living in space. Cosmonauts aboard the stations performed a variety of experiments in astronomy, biology, and Earth science. Salyut 6 and Salyut 7 each had two docking ports. One crew could dock a spacecraft to one end. A replacement crew could dock to the other end. | physics |
The result of what, in places like the amazon rainforest, is that food will be harder to produce, clean water will be harder to find, and development of new medicines will become slower? | sunlight | environmnental loss | seismic map | biodiversity loss | percent of the Amazon rainforest was lost. Rates are higher in other tropical rainforests. What we are likely to notice on a day-to-day basis as a result of biodiversity loss is that food will be more difficult to produce, clean water will be more difficult to find, and the rate of development of new medicines will become slower, as we depend upon other species for much of these services. This increased loss of biodiversity is almost entirely a result of human activities as we destroy species’ habitats, introduce disruptive species into ecosystems, hunt some species to extinction, continue to warm the planet with greenhouse gases, and influence nature in other ways. Slowing the loss of biodiversity is within our abilities if we make dramatic changes in our consumptive behavior and identify and protect the elements of our ecosystems that we depend on for our lives and welfare. | geography |
What does rising and sinking air influence in a region? | tides | temperature | erosion | precipitation | Rising and sinking air can influence the precipitation of a region. | physics |
Refracting and reflecting telescopes are optical telescopes that use lenses to gather what? | sound | electricity | oxygen decreases | light | Refracting and reflecting telescopes are optical telescopes that use lenses to gather light. | physics |
Via what process do substance move from one cell to another? | Longest Point | herbivore | fractional | plasmodesmata | biology |
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What is a stellar remnant that is very dense? | white star | asteroids | the sun | white dwarf | A white dwarf is a stellar remnant that is very dense. A white dwarf's mass is comparable to the Sun and its volume is comparable to that of Earth. The very low brightness of a white dwarf comes from the emission of stored heat energy. | physics |
What methods allow scientists to add to scientific knowledge and gain a better understanding of the world? | in fours | early investigations | slow investigations | through investigations | Investigations are at the heart of science. They are how scientists add to scientific knowledge and gain a better understanding of the world. Scientific investigations produce evidence that helps answer questions. Even if the evidence cannot provide answers, it may still be useful. It may lead to new questions for investigation. As more knowledge is discovered, science advances. | physics |
What is the largest level of organization? | chemical changes | organelle | particulates | organism | Levels of organization, from the atom (smallest) to the organism (largest). Notice that organelles are inside a cell, and organs are inside an organism. | physics |
Living species of chordates are classified into three major subphyla: vertebrata, urochordata, and what? | xerophyte | hottest known chameleon | Cortisol | cephalochordata | Living species of chordates are classified into three major subphyla: Vertebrata, Urochordata, and Cephalochordata. Vertebrates are all chordates that have a backbone. The other two subphyla are invertebrate chordates that lack a backbone. | biology |
What force explains why a tennis ball bounces differently on different surfaces, and shoes slip on some surfaces but stick on others? | temperature | receding hair | vibration | friction | Tennis is played on a variety of court surfaces: grass, clay, hardcourt, and even carpet. Players know that matches on different surfaces are distinctly different games. The ball bounces differently, and shoes slip on some surfaces but stick on others. These differences are a result of friction. | physics |
The term ion applies to entire molecules that are? | neutrally charged | iodinic hydrogen | positively charged protons | electrically charged | chemistry |
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Silicon and germanium react with nitrogen at high temperature to form what? | ethylene | oxides | carbonates | nitrides | The cavities normally contain hydrated cations that are loosely bound to the oxygen atoms of the negatively charged framework by electrostatic interactions. The sizes and arrangements of the channels and cavities differ in different types of zeolites. For example, in zeolite A the aluminosilicate cages are arranged in a cubic fashion, and the channels connecting the cavities intersect at right angles. In contrast, the cavities in faujasite are much larger, and the channels intersect at 120° angles. In these idealized models, the oxygen atoms that connect each pair of silicon atoms have been omitted. Silicon and germanium react with nitrogen at high temperature to form nitrides(M3N4): Equation 22.26. | chemistry |
What bond is the force of attraction that holds together oppositely charged ions? | liquid reaction | electrodes | sound | ionic | An ionic bond is the force of attraction that holds together oppositely charged ions. It forms when atoms of a metal transfer electrons to atoms of a nonmetal. When this happens, the atoms become oppositely charged ions. | physics |
What is the pairing of an adult male to an adult female to produce young? | chewing | evolution | backbones | mating | Some of the most important animal behaviors involve mating. Mating is the pairing of an adult male and female to produce young. Adults that are most successful at attracting a mate are most likely to have offspring. Traits that help animals attract a mate and have offspring increase their fitness. As the genes that encode these traits are passed to the next generation, the traits will become more common in the population. | biology |
The cell expels waste and other particles through a process called what? | reflection hormones | moles and lungfish | metamorphisis | exocytosis | 3.6 Active Transport The combined gradient that affects an ion includes its concentration gradient and its electrical gradient. Living cells need certain substances in concentrations greater than they exist in the extracellular space. Moving substances up their electrochemical gradients requires energy from the cell. Active transport uses energy stored in ATP to fuel the transport. Active transport of small molecular-size material uses integral proteins in the cell membrane to move the material—these proteins are analogous to pumps. Some pumps, which carry out primary active transport, couple directly with ATP to drive their action. In secondary transport, energy from primary transport can be used to move another substance into the cell and up its concentration gradient. Endocytosis methods require the direct use of ATP to fuel the transport of large particles such as macromolecules; parts of cells or whole cells can be engulfed by other cells in a process called phagocytosis. In phagocytosis, a portion of the membrane invaginates and flows around the particle, eventually pinching off and leaving the particle wholly enclosed by an envelope of plasma membrane. Vacuoles are broken down by the cell, with the particles used as food or dispatched in some other way. Pinocytosis is a similar process on a smaller scale. The cell expels waste and other particles through the reverse process, exocytosis. Wastes are moved outside the cell, pushing a membranous vesicle to the plasma membrane, allowing the vesicle to fuse with the membrane and incorporating itself into the membrane structure, releasing its contents to the exterior of the cell. | biology |
What are diodes, transistors, and integrated circuits examples of? | uniformly | converging lens | radio parts | electronic components | Electronic components are the parts used in electronic devices. They are made of p-type and n-type semiconductors. Examples of electronic components include diodes, transistors, and integrated circuits (microchips). | physics |
Shedding of dead cells ensures constant renewal of what outer layer of the skin? | ontology | scale | flightlessness | epidermis | The skin consists of two distinct layers, an outer layer called the epidermis and an inner layer called the dermis. The epidermis is constantly being renewed as dead cells on the surface are shed. This layer contains melanin-producing melanocytes. The dermis contains blood vessels, nerve endings, hair follicles, and sebaceous and sweat glands. | biology |
What causes cumulus clouds to grow upward? | saccule | mechanical | superconductors | convection currents | Cumulus clouds are white and puffy. Convection currents make them grow upward and they may grow very tall. When they produce rain, they are called cumulonimbus. | physics |
What term is used to describe a region getting significantly less precipitation than normal for an extended period of time? | their stems | soil erosion | inches | drought | Droughts also depend on what is normal for a region. A region that gets significantly less precipitation than normal for an extended period of time is in drought. The Southern United States is experiencing an ongoing and prolonged drought. | geography |
What is the name for compounds that contain only carbon and hydrogen? | carbides | particles | carbohydrates | hydrocarbons | The fuel that burns in a combustion reaction contains compounds called hydrocarbons. Hydrocarbons are compounds that contain only carbon (C) and hydrogen (H). The charcoal pictured in the Figure above consists of hydrocarbons. So do fossil fuels such as natural gas. Natural gas is a fuel that is commonly used in home furnaces and gas stoves. The main component of natural gas is the hydrocarbon called methane (CH 4 ). You can see a methane flame in the Figure below . The combustion of methane is represented by the equation:. | chemistry |
What human disease is caused by a defective enzyme that is unable to produce melanin, the pigment responsible for the color of skin and hair? | Parietal | hemophilia | anemia | albinism | untreated, it produces severe brain damage and mental retardation. Albinism is caused by a defective enzyme that is unable to produce melanin, the pigment responsible for the color of skin and hair. Cystic fibrosis, the most common inherited disease in the United States, blocks pancreatic function and causes thick mucus secretions that make breathing difficult. An area of intense research in combating cancer involves the synthesis of drugs that stop uncontrolled cell growth by interfering with DNA replication. | biology |
Individuals with sickle cell anemia have crescent-shaped what? | into the vans deferens | glial cells | the component map | red blood cells | Figure 39.21 Individuals with sickle cell anemia have crescent-shaped red blood cells. (credit: modification of work by Ed Uthman; scale-bar data from Matt Russell). | biology |
Nearly all weather occurs in the lower part of what? | running water | the mesosphere | high energy | the atmosphere | All weather takes place in the atmosphere. Nearly all of it in the lower atmosphere. Weather refers to the conditions of the atmosphere at a given time and place. Climate is the average of weather over a long time. | geography |
For skeletal development, the most common template is what? | collagen | calcium | membrane | cartilage | Cartilage Templates Bone is a replacement tissue; that is, it uses a model tissue on which to lay down its mineral matrix. For skeletal development, the most common template is cartilage. During fetal development, a framework is laid down that determines where bones will form. This framework is a flexible, semi-solid matrix produced by chondroblasts and consists of hyaluronic acid, chondroitin sulfate, collagen fibers, and water. As the matrix surrounds and isolates chondroblasts, they are called chondrocytes. Unlike most connective tissues, cartilage is avascular, meaning that it has no blood vessels supplying nutrients and removing metabolic wastes. All of these functions are carried on by diffusion through the matrix. This is why damaged cartilage does not repair itself as readily as most tissues do. Throughout fetal development and into childhood growth and development, bone forms on the cartilaginous matrix. By the time a fetus is born, most of the cartilage has been replaced with bone. Some additional cartilage will be replaced throughout childhood, and some cartilage remains in the adult skeleton. | biology |
The body's second line of defense against pathogens includes which response? | evolutionary | reaction | inspect | inflammatory | The body's second line of defense against pathogens includes the inflammatory response. If bacteria enter the skin through a scrape, the area may become red, warm, and painful. These are signs of inflammation. Inflammation is one way the body reacts to infections or injuries. Inflammation is caused by chemicals that are released when skin or other tissues are damaged. The chemicals cause nearby blood vessels to dilate, or expand. This increases blood flow to the damaged area, which makes the area red and slightly warm. The chemicals also attract white blood cells called neutrophils to the wound and cause them to leak out of blood vessels into the damaged tissue. | biology |
Hiv is a retrovirus, which means it reverse transcribes its rna genome into what? | amino acid chains | atp | Muscular system | dna | Figure 17.5 Viruses can be complex in shape or relatively simple. This figure shows three relatively complex virions: the bacteriophage T4, with its DNA-containing head group and tail fibers that attach to host cells; adenovirus, which uses spikes from its capsid to bind to the host cells; and HIV, which uses glycoproteins embedded in its envelope to do so. Notice that HIV has proteins called matrix proteins, internal to the envelope, which help stabilize virion shape. HIV is a retrovirus, which means it reverse transcribes its RNA genome into DNA, which is then spliced into the host’s DNA. (credit “bacteriophage, adenovirus”: modification of work by NCBI, NIH; credit “HIV retrovirus”: modification of work by NIAID, NIH). | biology |
Plants can tell the time of day and time of year by sensing and using various wavelengths of what | cranial nerves | vertical line system | thigmotropism | sunlight | Plant Responses to Light Plants have a number of sophisticated uses for light that go far beyond their ability to photosynthesize low-molecularweight sugars using only carbon dioxide, light, and water. Photomorphogenesis is the growth and development of plants in response to light. It allows plants to optimize their use of light and space. Photoperiodism is the ability to use light to track time. Plants can tell the time of day and time of year by sensing and using various wavelengths of sunlight. Phototropism is a directional response that allows plants to grow towards, or even away from, light. The sensing of light in the environment is important to plants; it can be crucial for competition and survival. The response of plants to light is mediated by different photoreceptors, which are comprised of a protein covalently bonded to a lightabsorbing pigment called a chromophore. Together, the two are called a chromoprotein. | biology |
In eukaryotes, the major mechanism for shuffling genes is what? | fluids | dendrite | Sex, Love, Food | sexual reproduction | Sexual reproduction In eukaryotes, the major mechanism for shuffling genes is sexual reproduction. Because sex (usually) requires that organisms cooperate sex represents an example of social evolution. So what are the benefits of sexual reproduction? 342 Sexual reproduction involves the alternation of diploid (two copies of each chromosome) and haploid (one copy of each chromosome) cell types. In a diploid cell, the two copies of a particular gene can be different, the the organisms is said to be heterozygous for that gene. Different alleles can (but do not necessarily do) encode functionally distinct gene products and can be associated with different phenotypes (discussed in greater detail in the future two-semester version). We can then characterize different alleles with respect to one one another. Assume that allele-1 is associated with phenotype-1 342. | biology |
The vas deferens and ejaculatory ducts transport sperm from the epididymes to the urethra in what system? | paleontologists | pressure the eye | active respiration | male reproductive system | In addition to these organs, the male reproductive system consists of a series of ducts and glands. Ducts include the vas deferens and ejaculatory ducts. They transport sperm from the epididymes to the urethra in the penis. Glands include the seminal vesicles and prostate gland. They secrete substances that become part of semen. | biology |
What do nearly all animals have in common with regards to digestion? | problematic digestion of food | the pit | complete digestion of food | internal digestion of food | Virtually all animals have internal digestion of food. Animals consume other organisms and may use special tissues and organs to digest them. (Many other organisms absorb nutrients directly from the environment. ). | biology |
What are the secretions released by the endocrine glands called? | Posion | processed acid sequence | fluids | hormones | Endocrine Glands The secretions of endocrine glands are called hormones. Hormones are released into the interstitial fluid, diffused into the bloodstream, and delivered to targets, in other words, cells that have receptors to bind the hormones. The endocrine system is part of a major regulatory system coordinating the regulation and integration of body responses. A few examples of endocrine glands include the anterior pituitary, thymus, adrenal cortex, and gonads. | biology |
What are chromosomes in the same pair called? | aquatic and land | lithium | adult breast growth | homologous chromosomes | In sexually reproducing species, chromosomes are present in cells in pairs. Chromosomes in the same pair are called homologous chromosomes. They have the same genes at the same loci. These may be the same or different alleles. During meiosis, when gametes are produced, homologous chromosomes separate. They go to different gametes. Thus, the alleles for each gene also go to different gametes. | biology |
What do you call plastids that contain the green pigment chlorophyll? | Leucoplasts | Gerontoplasts | Chromoplasts | chloroplasts | Chloroplasts are plastids that contain the green pigment chlorophyll. They capture light energy from the sun and use it to make food. A chloroplast is shown in Figure above . | biology |
What important and unusual physical property (for birds) do ostriches and penguins share? | the passenger piegon | insecticides | opinion | flightlessness | There are about 10,000 living species of birds. Almost all of them can fly. Flying birds are classified in 29 orders. Most species belong to the order of perching birds. A few birds are flightless, such as the ostrich and penguin, but they evolved from a flying ancestor. | biology |
What are changes in membrane potential that vary continuously with the strength of a stimulus are known as? | kinetic energy | reverse potentials | sensory overload | graded potentials | biology |
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The moon has a crust, mantle, and a? | mountain range | ice cap | magnetic field | core | The Moon has a crust, mantle, and core. | physics |
What type of coal is formed at lower temperatures? | chemical change | clean | electron movement | bituminous | Coal has different grades. Bituminous coal forms at lower temperatures. It contains a lot of sulfur. When it is burned, it causes a lot of pollution. Anthracite coal forms under higher temperatures. This drives off the sulfur, and the coal burns more cleanly. | physics |
What can sodium ions not pass through? | narrowness lipid bilayer | Digestion | ionic hybridization | nonpolar lipid bilayer | As an example, even though sodium ions (Na+) are highly concentrated outside of cells, these electrolytes are charged and cannot pass through the nonpolar lipid bilayer of the membrane. Their diffusion is facilitated by membrane proteins that form sodium channels (or “pores”), so that Na+ ions can move down their concentration gradient from outside the cells to inside the cells. There are many other solutes that must undergo facilitated diffusion to move into a cell, such as amino acids, or to move out of a cell, such as wastes. Because facilitated diffusion is a passive process, it does not require energy expenditure by the cell. Water also can move freely across the cell membrane of all cells, either through protein channels or by slipping between the lipid tails of the membrane itself. Osmosis is the diffusion of water through a semipermeable membrane (Figure 3.7). | chemistry |
What happens when the kidneys cannot remove wastes from the blood? | choanocyte failure | tissue failure | intestinal failure | kidney failure | Kidney failure happens when the kidneys cannot remove wastes from the blood. If the kidneys are unable to filter wastes from the blood, the wastes build up in the body. Kidney failure can be caused by an accident that injures the kidneys, the loss of a lot of blood, or by some drugs and poisons. Kidney failure may lead to permanent loss of kidney function. But if the kidneys are not seriously damaged, they may recover. | biology |
What is another name for nearsightedness? | presbyopia | hyperopia | elongated clusters | myopia | Myopia is also called nearsightedness. It affects about one third of people. People with myopia can see nearby objects clearly, but distant objects appear blurry. The picture below shows how a person with myopia might see two boys that are a few meters away ( Figure below ). | physics |
What is the innermost layer of the sun called? | Photosphere | Convection Zone | they are double | the core | Because the Sun is not solid, it does not have a defined outer boundary. It does, however, have a definite internal structure with identifiable layers ( Figure below ). Since the layers are not solid, the boundaries are fuzzy and indistinct. From inward to outward, the layers are: the core, the radiative zone, and the convection zone. | physics |
What device is used to study charge? | the stellar field | assumptions | physical reaction only | electroscope | An electroscope is a device used to study charge. When a positively charged object (the rod) nears the upper post, electrons flow to the top of the jar leaving the two gold leaves postivley charged. The leaves repel each other since both hold postive, like charges. The VSEPR theory says that electron pairs, also a set of like charges, will repel each other such that the shape of the molecule will adjust so that the valence electron-pairs stay as far apart from each other as possible. | physics |
What term is used to describe large numbers of species that go extinct in a short amount of time? | species extinction | formation extinction | organic extinction | mass extinction | Sometimes large numbers of species go extinct in a short amount of time. This is a mass extinction . The causes of different mass extinctions are different: collisions with comets or asteroids, massive volcanic eruptions, or rapidly changing climate are all possible causes of some of these disasters ( Figure below ). | biology |
What is the tiny male gametophyte enclosed in a tough capsule? | calcium | Cell Capsule | nitrogen | pollen | Pollen is a tiny male gametophyte enclosed in a tough capsule. Pollen carries sperm to an ovule while preventing the sperm from drying out. Pollen grains can't swim, but they are very light, so the wind can carry them. Therefore, they can travel through air instead of water. | biology |
When zinc reacts with hydrochloric acid, the reaction bubbles vigorously as which type of gas is produced? | biogeochemical | chlorine | oxygen | hydrogren | When zinc reacts with hydrochloric acid, the reaction bubbles vigorously as hydrogen gas is produced ( Figure below ). The production of a gas is also an indication that a chemical reaction may be occurring. | chemistry |
Structural adaptations in flying animals often contribute to reduced what? | endoplasmic cells | sperm cells | nonviable | body mass | biology |
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What diagram is used to reflect evolutionary relationships among organisms or groups of organisms? | paleontology | relationships tree | reeds | phylogenetic tree | Classification and Phylogeny Scientists use a tool called a phylogenetic tree to show the evolutionary pathways and relationships between organisms. A phylogenetic tree is a diagram used to reflect evolutionary relationships among organisms or groups of organisms. The hierarchical classification of groups nested within more inclusive groups is reflected in diagrams. Scientists consider phylogenetic trees to be a hypothesis of the evolutionary past because one cannot go back through time to confirm the proposed relationships. Unlike with a taxonomic classification, a phylogenetic tree can be read like a map of evolutionary history, as shown in Figure 12.4. Shared characteristics are used to construct phylogenetic trees. The point where a split occurs in a tree, called a branch point, represents where a single lineage evolved into distinct new ones. Many phylogenetic trees have a single branch point at the base representing a common ancestor of all the branches in the tree. Scientists call such trees rooted, which means there is a single ancestral taxon at the base of a phylogenetic tree to which all organisms represented in the diagram descend from. When two lineages stem from the same branch point, they are called sister taxa, for example the two species of orangutans. A branch point with more than two groups illustrates a situation for which scientists have not definitively determined relationships. An example is illustrated by the three branches leading to the gorilla subspecies; their exact relationships are not yet understood. It is important to note that sister taxa share an ancestor, which does not mean that one taxon evolved from the other. The branch point, or split, represents a common ancestor that existed in the past, but that no longer exists. Humans did not evolve from chimpanzees (nor did chimpanzees evolve from humans) although they are our closest living relatives. Both humans and chimpanzees evolved from a common ancestor that lived, scientists believe, six million years ago and looked different from both modern chimpanzees and modern humans. | biology |
What is the energy called that is stored in matter? | sensing lenses | stored energy | possible | potential | Potential energy is energy stored in matter. | physics |
What is the term for traits that show wide variation, such as height, skin color, and eye color? | recessive traits | maladaptive traits | inherited traits | polygenic traits | Usually, traits are polygenic when there is wide variation in the trait. For example, humans can be many different sizes. Height is a polygenic trait, controlled by at least three genes with six alleles. If you are dominant for all of the alleles for height, then you will be very tall. There is also a wide range of skin color across people. Skin color is also a polygenic trait, as are hair and eye color. | biology |
Which system in the human body consists of the heart, a network of blood vessels, and blood? | molecules of carbohydrates | cardiac system | industrial and demand | cardiovascular system | The cardiovascular system consists of the heart, a network of blood vessels, and blood. Blood is a liquid tissue. The heart is a pump that keeps blood flowing through the vessels of the system. | biology |
Volume is another way of measuring what? | height | tone canal | weight | material | Volume is another way of measuring material. Gases cannot be easily weighed, but their volume can be determined quickly and accurately. Liquid chemicals as well as foods and beverages are also sold by volume. Gasoline for our cars and trucks is sold by the gallon. At the grocery store, we can buy a gallon of milk or a two-liter bottle of soda pop. | physics |
What do you call a science that aims to find solutions to practical problems? | evolved science | zero population growth | experimental science | applied science | Life science may be basic or applied science. The aim of basic science is to gain new knowledge and a better understanding of the natural world. The aim of applied science is to find solutions to practical problems. | physics |
What term describes weathering that occurs as water expands when it freezes, wedging apart rock? | erosion | chemical weathering | geiger | mechanical weathering | form of mechanical weathering that occurs as water expands when it freezes, wedging apart rock. | physics |
How many pairs of chromosomes are found in human cells? | 13 | 25 | 24 | 23 | Human cells have 23 pairs of chromosomes, and each chromosome within a pair is called a homologous chromosome . For each of the 23 chromosome pairs, you received one chromosome from your father and one chromosome from your mother. Alleles are alternate forms of genes found on chromosomes. Homologous chromosomes have the same genes, though they may have different alleles. So, though homologous chromosomes are very similar, they are not identical. The homologous chromosomes are separated when gametes are formed. Therefore, gametes have only 23 chromosomes, not 23 pairs. | biology |
An aqueous solution is a homogeneous mixture in which the most abundant component is what? | blood | drug | biochemical compounds | water | An aqueous solution is a homogeneous mixture in which the most abundant component is water. The other substance(s) are typically introduced in a solid or liquid form and mixed into the water until they are evenly distributed. For example, if we placed a sample of ethanol in water and mixed it homogeneously, we would have a solution. Table salt mixed with water is another example of a solution. More generally, a solution is a homogeneous mixture. The solution component that is present in the largest amount is called the solvent , and all other substances are referred to as solutes . In aqueous solutions, water is always the solvent. | chemistry |
What happens to light when it reflects from a rough surface? | atomic volume unit | 10 | elliptical | gets diffused | Figure 25.5 Light is diffused when it reflects from a rough surface. Here many parallel rays are incident, but they are reflected at many different angles since the surface is rough. | physics |
Isothermal expansion is a process occurring without a change in? | sunlight insulators | output | electrification | temperature | isothermal expansion is a process occurring without a change in temperature. | physics |
Nearly all fish reproduce sexually and have what? | annelids | modified sexes | flexible sexes | separate sexes | Nearly all fish reproduce sexually and have separate sexes. | biology |
Cilia and flagella are generally associated with what function in organisms, whether the function is internal or external? | sight | digestion | reproduction | movement | Cilia ( cilium , singular) are made up of microtubule containing extensions of the cell membrane. Although both cilia and flagella are used for movement, cilia are much shorter than flagella. Cilia cover the surface of some single-celled organisms, such as paramecium. Their cilia beat together to move the little animal-like protists through the water. In multicellular animals, including humans, cilia are usually found in large numbers on a single surface of cells. Multicellular animals' cilia usually move materials inside the body. For example, the mucociliary escalator of the respiratory system is made up of mucus-secreting ciliated cells that line the trachea and bronchi. These ciliated cells, shown in Figure below , move mucus away from the lungs. This mucus catches spores, bacteria, and debris and moves to the esophagus, where it is swallowed. | biology |
Do particles collide more in two reactants when they are both in fluid forms or solid forms? | solid | plasma | neither | fluid | Phase and Surface Area Effects When two reactants are in the same fluid phase, their particles collide more frequently than when one or both reactants are solids (or when they are in different fluids that do not mix). If the reactants are uniformly dispersed in a single homogeneous solution, then the number of collisions per unit time depends on concentration and temperature, as we have just seen. If the reaction is heterogeneous, however, the reactants are in two different phases, and collisions between the reactants can occur only at interfaces between phases. The number of collisions between reactants per unit time is substantially reduced relative to the homogeneous case, and, hence, so is the reaction rate. The reaction rate of a heterogeneous reaction depends on the surface area of the more condensed phase. Automobile engines use surface area effects to increase reaction rates. Gasoline is injected into each cylinder, where it combusts on ignition by a spark from the spark plug. The gasoline is injected in the form of microscopic droplets because in that form it has a much larger surface area and can burn much more rapidly than if it were fed into the cylinder as a stream. Similarly, a pile of finely divided flour burns slowly (or not at all), but spraying finely divided flour into a flame produces a vigorous reaction (Figure 14.3 "The Effect of Surface Area on Reaction Rates"). Similar phenomena are partially responsible for dust explosions that occasionally destroy grain elevators or coal mines. | physics |
The process of moving from areas of high amounts to areas of low amounts is called what? | 4 | farsightedness | slash-and-burn | diffusion | They will all blend together. The dyes will move through the water until an even distribution is achieved. The process of moving from areas of high amounts to areas of low amounts is called diffusion. | geography |
Vascular tissue allowed these plants to do what? | live shorter | grow smaller | have more flowers | grow taller | Seedless vascular plants evolved to have vascular tissue after the nonvascular plants but do not have seeds. Examples include the ferns, whisk ferns, club mosses, and horsetails. Vascular tissue allowed these plants to grow taller. | biology |
What were the first forms of life on earth? | vestigial organs | 22 % | eukaryotes | prokaryotes | Prokaryotes, the First Inhabitants of Earth When and where did life begin? What were the conditions on Earth when life began? Prokaryotes were the first forms of life on Earth, and they existed for billions of years before plants and animals appeared. The Earth and its moon are thought to be about 4.54 billion years old. This estimate is based on evidence from radiometric dating of meteorite material together with other substrate material from Earth and the moon. Early Earth had a very different atmosphere (contained less molecular oxygen) than it does today and was subjected to strong radiation; thus, the first organisms would have flourished where they were more protected, such as in ocean depths or beneath the surface of the Earth. At this time too, strong volcanic activity was common on Earth, so it is likely that these first organisms—the first prokaryotes—were adapted to very high temperatures. Early Earth was prone to geological upheaval and volcanic eruption, and was subject to bombardment by mutagenic radiation from the sun. The first organisms were prokaryotes that could withstand these harsh conditions. Microbial Mats Microbial mats or large biofilms may represent the earliest forms of life on Earth; there is fossil evidence of their presence starting about 3.5 billion years ago. A microbial mat is a multi-layered sheet of prokaryotes (Figure 22.2) that includes mostly bacteria, but also archaea. Microbial mats are a few centimeters thick, and they typically grow where different types of materials interface, mostly on moist surfaces. The various types of prokaryotes that comprise them carry out different metabolic pathways, and that is the reason for their various colors. Prokaryotes in a microbial mat are held together by a glue-like sticky substance that they secrete called extracellular matrix. The first microbial mats likely obtained their energy from chemicals found near hydrothermal vents. A hydrothermal vent is a breakage or fissure in the Earth’s surface that releases geothermally heated water. With the evolution of photosynthesis about 3 billion years ago, some prokaryotes in microbial mats came to use a more widely available energy source—sunlight—whereas others were still dependent on chemicals from hydrothermal vents for energy and food. | biology |
What warms the base of the mantle creating convection currents there? | cylindrical | mantle soil | the hot regenerate | the hot core | The hot core warms the base of the mantle, which creates convection currents in the mantle. | physics |
What do we call an incorrect test result that should have been positive? | twenty | external positive | false positive | false negative | Cancer Proteomics Genomes and proteomes of patients suffering from specific diseases are being studied to understand the genetic basis of the disease. The most prominent disease being studied with proteomic approaches is cancer. Proteomic approaches are being used to improve screening and early detection of cancer; this is achieved by identifying proteins whose expression is affected by the disease process. An individual protein is called a biomarker, whereas a set of proteins with altered expression levels is called a protein signature. For a biomarker or protein signature to be useful as a candidate for early screening and detection of a cancer, it must be secreted in body fluids, such as sweat, blood, or urine, such that largescale screenings can be performed in a non-invasive fashion. The current problem with using biomarkers for the early detection of cancer is the high rate of false-negative results. A false negative is an incorrect test result that should have been positive. In other words, many cases of cancer go undetected, which makes biomarkers unreliable. Some examples of protein biomarkers used in cancer detection are CA-125 for ovarian cancer and PSA for prostate cancer. Protein signatures may be more reliable than biomarkers to detect cancer cells. Proteomics is also being used to develop individualized treatment plans, which involves the prediction of whether or not an individual will respond to specific drugs and the side effects that the individual may experience. Proteomics is also being used to predict the possibility of disease recurrence. The National Cancer Institute has developed programs to improve the detection and treatment of cancer. The Clinical Proteomic Technologies for Cancer and the Early Detection Research Network are efforts to identify protein signatures specific to different types of cancers. The Biomedical Proteomics Program is designed to identify protein signatures and design effective therapies for cancer patients. | biology |
The conversion factor between solubility and molar solubility of a compound is known as what? | molar value | mass effect | stochastic mass | molar mass | Solubility is normally expressed in g/L of saturated solution. However, solubility can also be expressed as the moles per liter. Molar solubility is the number of moles of solute in one liter of saturated solution. In other words, the molar solubility of a given compound represents the highest molarity solution that is possible for that compound. The molar mass of a compound is the conversion factor between solubility and molar solubility. Given that the solubility of Zn(OH) 2 is 4.2 × 10 -4 g/L, the molar solubility can be calculated as shown below:. | chemistry |
What describes the process of vesicles fusing with the plasma membrane and releasing their contents to the outside of the cell? | expulsion | autolysis | suggestive immune system | exocytosis | Exocytosis describes the process of vesicles fusing with the plasma membrane and releasing their contents to the outside of the cell, as shown in Figure below . Exocytosis occurs when a cell produces substances for export, such as a protein, or when the cell is getting rid of a waste product or a toxin. Newly made membrane proteins and membrane lipids are moved to the plasma membrane by exocytosis. | biology |
Out of the four ways that allele frequencies of a population can be changed, which way is caused by individuals leaving or joining the population? | main generation | chemosynthetic bacteria | thyroxine | gene flow | 11.2 Mechanisms of Evolution There are four factors that can change the allele frequencies of a population. Natural selection works by selecting for alleles that confer beneficial traits or behaviors, while selecting against those for deleterious qualities. Mutations introduce new alleles into a population. Genetic drift stems from the chance occurrence that some individuals have more offspring than others and results in changes in allele frequencies that are random in direction. When individuals leave or join the population, allele frequencies can change as a result of gene flow. | biology |
What kind of bond doesn't form molecules, but instead forms crystals? | atmospheric bonds | the hop | iron and magnesium | ionic bonds | Ionic compounds contain ions of metals and nonmetals held together by ionic bonds. Ionic compounds do not form molecules. Instead, many positive and negative ions bond together to form a structure called a crystal. You can see an example of a crystal in Figure below . It shows the ionic compound sodium chloride. Positive sodium ions (Na + ) alternate with negative chloride ions (Cl - ). The oppositely charged ions are strongly attracted to each other. | chemistry |
Where does the natural synthesis of lactose occur? | liver tissue | ovarian tissue | nervous tissue | mammary tissue | Lactose Lactose is known as milk sugar because it occurs in the milk of humans, cows, and other mammals. In fact, the natural synthesis of lactose occurs only in mammary tissue, whereas most other carbohydrates are plant products. Human milk contains about 7.5% lactose, and cow’s milk contains about 4.5%. This sugar is one of the lowest ranking in terms of sweetness, being about one-sixth as sweet as sucrose (seeTable 16.1 "The Relative Sweetness of Some Compounds (Sucrose = 100)" in Section 16.3 "Important Hexoses"). Lactose is produced commercially from whey, a by-product in the manufacture of cheese. It is important as an infant food and in the production of penicillin. Lactose is a reducing sugar composed of one molecule of D-galactose and one molecule of D-glucose joined by a β-1,4-glycosidic bond (the bond from the anomeric carbon of the first monosaccharide unit being directed upward). The two monosaccharides are obtained from lactose by acid hydrolysis or the catalytic action of the enzyme lactase:. | geography |
The ratio between the radii of a wheel and axle determines what? | theoretical mechanical advantage | fundamental mechanical advantage | introduced mechanical advantage | ideal mechanical advantage | Just like it sounds, a wheel and axle is composed of two connected cylinders of different diameters. Since the wheel has a larger radius (distance) than the axle, the axle will always have a larger force than the wheel. The ideal mechanical advantage of a wheel and axle is dependent on the ratio between the radii:. | physics |
What is the first stage of cellular respiration called? | population multiplication rate | appetite | coral resources | glycolysis | When was the last time you enjoyed yogurt on your breakfast cereal, or had a tetanus shot? These experiences may appear unconnected, but both relate to bacteria which do not use oxygen to make ATP. In fact, tetanus bacteria cannot survive if oxygen is present. However, Lactobacillus acidophilus (bacteria which make yogurt) and Clostridium tetani (bacteria which cause tetanus or lockjaw) share with nearly all organisms the first stage of cellular respiration, glycolysis ( Figure below ). Because glycolysis is universal, whereas aerobic (oxygen-requiring) cellular respiration is not, most biologists consider it to be the most fundamental and primitive pathway for making ATP. | biology |
Many species use their body shape and coloration to avoid being detected by what? | bone | origin selection | darwinian trait | predators | Many species use their body shape and coloration to avoid being detected by predators. The tropical walking stick is an insect with the coloration and body shape of a twig, which makes it very hard to see when it is stationary against a background of real twigs (Figure 19.15a). In another example, the chameleon can change its color to match its surroundings (Figure 19.15b). | biology |
A reference point is used in measurement to make what? | large mass | refrigerant | the ocean | estimation | Estimation, as used in measurement, is the process of referencing a physical quantity in terms of a calibration or reference point. All measurement devices have reference marks of some kind. | physics |
Why do adult herbivores in a herd surround their young? | mitochondrion | acidic buildup | fluorescent pigments | to protect them as they are vulnerable to predators | Herbivores such as zebras and elephants live in herds . Adults in the herd surround and protect the young, who are most vulnerable to predators. | biology |
When orders are sent from your brain to your legs, these signals pass through what type of cells? | number of chromosomes | arbitrary mutations | molecules | nerve cells | Cells, like these nerve cells, do not work in isolation. To send orders from your brain to your legs, for example, signals pass through many nerve cells. These cells work together to perform a similar function. Just as muscle cells work together, bone cells and many other cells do as well. A group of similar cells that work together is known as a tissue. | biology |
What is the leading cause of soil erosion? | glacier movement | tidal winds | volcanic explosions | running water | The same agents that erode landscapes also erode soil. They are water, wind, ice, or gravity. Running water is the leading cause of soil erosion. Water is abundant and has a lot of power. Wind is also a leading cause of soil erosion. Wind can pick up soil and blow it far away. | geography |
What class of organisms help decompose matter to release nutrients and make nutritious food for other organisms ? | coral | cell production therapy | natural selection | fungi | If so, then you have encountered fungi . Fungi are organisms that belong to the Kingdom Fungi ( Figure below ). Our environment needs fungi. Fungi help decompose matter to release nutrients and make nutritious food for other organisms. Fungi are all around us and are useful in many ways. | biology |
A pedigree is a chart which shows the inheritance of a trait over several what? | tree tops | cardiologists | micelles | generations | A pedigree is a chart which shows the inheritance of a trait over several generations. A pedigree is commonly created for families, as it can be used to outlines the inheritance patterns of familial traits or genetic disorders. It can be used to demonstrate autosomal dominant or recessive inheritance, or sex-linked inheritance. Figure below shows a pedigree depicting recessive inheritance of a disorder through three generations. The trait is thought to be recessive as for the two individuals with the trait, neither has a parent who also has the trait. Geneticists may also be able to determine whether individuals with the trait in question are heterozygous or homozygous for the allele associated with the trait. When alleles are added to the pedigree shown ( A or a ), recessive inheritance in conformed. | biology |
The release of calcium ions initiates what? | Thermal energy | nematodes | magnetic process | muscle contractions | The release of calcium ions initiates muscle contractions. Watch this video (http://openstaxcollege. org/l/calciumrole) to learn more about the role of calcium. (a) What are “T-tubules” and what is their role? (b) Please describe how actinbinding sites are made available for cross-bridging with myosin heads during contraction. | chemistry |
The electron released during beta decay is not an orbital electron but an electron whose origin was where? | destruction | outside the nucleus | connected to the nucleus | in the nucleus | The symbol represents an electron whose charge corresponds to and since it has no nucleons, . It must be carefully noted that the electron released during beta decay is NOT an orbital electron but an electron whose origin was in the nucleus. The process has one neutron becoming one proton and one electron and the electron being emitted as a beta particle. Since a neutron has been lost AND a proton has been gained, the mass number does not change. The atomic number, however, has increased one due to the gain of a proton. Therefore, as a result of beta decay, the daughter product will have the same mass number as the parent and an atomic number one greater than the parent. | physics |
What is created by the polymerization of glucose? | calories | juice | homocyclic compounds | cellulose | Zachary Wilson. Cellulose is created by the polymerization of glucose . CC BY-NC 3.0. | chemistry |
Fungi reproduce asexually by fragmentation and either sexually or asexually via what lightweight, windblown structures? | immune system disorders | stem cells | cocoon | spores | 23.25 Fungal Reproduction Fungi can reproduce in two ways. Firstly, they make asexually produce through fragmentation. This occurs when pieces of hyphae are broken off, which then grow into new mycelia. The second method is by spores. Spores are lightweight structures and windblown designed to be transported over long distances and by many mediums, such as on the bodies of insects and birds. They are additionally light enough to be blown away for hundreds of kilometers. Spores may be asexual and sexual. Their sexual properties can be analysed to classify the four phylla of fungi. | biology |