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Diabetes is a non-infectious disease in which the body is unable to control the amount of what in the blood? | protein | water | plasma | sugar | Diabetes is a non-infectious disease in which the body is unable to control the amount of sugar in the blood. People with diabetes have high blood sugar, either because their bodies do not produce enough insulin, or because their cells do not respond to insulin. Insulin is a hormone that helps cells take up sugar from the blood. Without enough insulin, the blood contains too much sugar. This can damage blood vessels and other cells throughout the body. The kidneys work hard to filter out and remove some of the extra sugar. This leads to frequent urination and excessive thirst. |
All living organisms are classified into one of six broad categories called what? | nobles | cities | tribes | kingdoms | The level of biodiversity found in the fossil record suggests that the last few million years include the period of greatest biodiversity in the Earth's history. However, not all scientists support this view, since there is a lot of uncertainty as to how strongly the fossil record is biased by the greater availability and preservation of more recent fossil-containing rock layers. Some researchers argue that modern biodiversity is not much different from biodiversity 300 million years ago. Estimates of the present global species diversity vary from 5 million to 30 million species, with a best estimate of somewhere near 10 million species. All living organisms are classified into one of the six kingdoms: Archaebacteria (Archaea), Eubacteria (Bacteria), Protista (Protists), Fungi, Plantae (Plants), and Animalia (Animals). |
What is the most common type of cancer in adult males? | lung cancer | stomach cancer | liver cancer | prostate cancer | Cancer is usually found in adults, especially in adults over the age of 50. The most common type of cancer in adult males is cancer of the prostate gland. The prostate gland is part of the male reproductive system. Prostate cancer makes up about one third of all cancers in men. The most common type of cancer in adult females is breast cancer. It makes up about one third of all cancers in women. In both men and women, lung cancer is the second most common type of cancer. Most cases of lung cancer happen in people who smoke. |
What occurs when an unstable nucleus emits an alpha particle and energy? | alpha radition | radar decay | nucleus decay | alpha decay | Alpha decay occurs when an unstable nucleus emits an alpha particle and energy. The diagram in Figure below represents alpha decay. An alpha particle contains two protons and two neutrons, giving it a charge of +2. A helium nucleus has two protons and two neutrons, so an alpha particle is represented in nuclear equations by the symbol . The superscript 4 is the mass number (2 protons + 2 neutrons). The subscript 2 is the charge of the particle as well as the number of protons. |
What molecule can be used by the body to synthesize cholesterol ? | chloride coa | ethylene coa | hydroxide coa | acetyl coa | Because of the link between high levels of cholesterol and heart disease, it is commonly seen by the general public as a “bad” molecule. However, cholesterol plays a vital role in the body, as both a structural component of cell membranes and a metabolic precursor to various steroid hormones. Only about 30% of the cholesterol in our bodies comes from our diet; the rest is synthesized in the liver, intestines, adrenal glands, and reproductive organs. The same acetyl CoA molecule that provides biochemical energy can also be used by the body to synthesize cholesterol. There are approximately twenty-two steps involved in the formation of cholesterol from acetyl CoA. |
Full siblings share how many genes with each other? | 25% | 75% | 100% | half | |
Which highly valuable substance found in jewelry has a density of about 19 g/cm^3? | silver | diamonds | rubies | gold | Samples that are the same size, but have different densities, will have different masses. Gold has a density of about 19 g/cm 3 . Pyrite has a density of only about 5 g/cm 3 . Quartz is even less dense than pyrite, and has a density of 2.7 g/cm 3 . If you picked up a piece of pyrite and a piece of quartz that were the same size, the pyrite would seem almost twice as heavy as the quartz. |
Sperm propel themselves through secretions in the uterus and enter what tube? | uterine | gaseous | ovarian | fallopian | A day or two after an ovary releases an egg, the egg may unite with a sperm. Sperm are deposited in the vagina during sexual intercourse. They propel themselves through secretions in the uterus and enter a fallopian tube. This is where fertilization normally takes place. |
What type of minerals are often found where seas once covered the land? | sea salt | magnesium | crystals | carbonate | Carbonate minerals are often found where seas once covered the land. Some carbonate minerals are very common. Calcite contains calcium, carbon, and oxygen. Have you ever been in a limestone cave or seen a marble tile? Calcite is in both limestone and marble. Azurite and malachite are also carbonate minerals. They contain copper instead of calcium. They are not as common as calcite. Malachite and azurite are used in jewelry; as you can see, they are very colorful ( Figure below ). |
How many amino acids generally consist in protien? | 67 or more | 13 or more | 7 or more | 100 or more | A polypeptide is a sequence of amino acids between ten and one hundred in length. A protein is a peptide that is greater than one hundred amino acids in length. Proteins are very prevalent in living organisms. Hair, skin, nails, muscles, and the hemoglobin in red blood cells are some of the important parts of your body that are made of different proteins. The wide array of chemical and physiological properties of proteins is a function of their amino acid sequences. Since proteins generally consist of one hundred or more amino acids, the number of amino acid sequences that are possible is virtually limitless. |
Rain, snow, sleet, and hail are all examples of what? | liquids | temperature | erosion | precipitation | |
Where would you find most pollution of ocean water? | trenches | midocean | poles | coastline | Ocean water is most polluted along coasts. That’s because pollution usually enters the water from land. Oil spills also pollute ocean water. |
Water can be a solid, liquid, and what other form? | plasma | ooze | square | gas | Water can be a solid, liquid, or a gas. |
What happens to a species when all of the individuals die out or evolve into a different species? | depletion | accumulation | selection | extinction | Species go extinct when all of the individuals die out or evolve into a different species. |
The viscosity of a liquid is a measure of what? | adaptability to surroundings | resistance to change form | ability to absorb flow | resistance to flow | When you pour a glass of water, or fill a car with gasoline, you observe that water and gasoline flow freely. But when you pour syrup on pancakes or add oil to a car engine, you note that syrup and motor oil do not flow as readily. The viscosity of a liquid is a measure of its resistance to flow. Water, gasoline, and other liquids that flow freely have a low viscosity. Honey, syrup, motor oil, and other liquids that do not flow freely, like those shown in Figure 10.15, have higher viscosities. We can measure viscosity by measuring the rate at which a metal ball falls through a liquid (the ball falls more slowly through a more viscous liquid) or by measuring the rate at which a liquid flows through a narrow tube (more viscous liquids flow more slowly). |
How is energy expressed when it is released in a chemical reaction? | as a positive number | as an equation | as a percentage | as negative number | When energy is released in a chemical reaction or process, that energy is expressed as a negative number. Figure below shows electron affinities in kJ/mol for the main group elements. |
What is the term for a structure within the cytoplasm that performs a specific job in the cell? | molecule | vacuole | nucleolus | organelle | Eukaryotic cells also contain other organelles besides the nucleus. An organelle is a structure within the cytoplasm that performs a specific job in the cell. Organelles called mitochondria, for example, provide energy to the cell, and organelles called vacuoles store substances in the cell. Organelles allow eukaryotic cells to carry out more functions than prokaryotic cells can. This allows eukaryotic cells to have greater cell specificity than prokaryotic cells. Ribosomes, the organelle where proteins are made, are the only organelles in prokaryotic cells. |
What part of a mature plant cell is responsible for storing substances like water, enzymes, and salts? | large vacuole | little vacuole | second vacuole | central vacuole | Most mature plant cells have a large central vacuole . This vacuole can make up as much as 90% of the cell’s volume. The central vacuole has a number of functions, including storing substances such as water, enzymes, and salts. It also helps plant tissues, such as stems and leaves, stay rigid and hold their shape. It even helps give flowers, like the ones in Figure below , their beautiful colors. |
Whereas each cell shares the same genome and dna sequence, each cell does not turn on, or express, the same set of what? | balls | babies | eggs | genes | Introduction Each somatic cell in the body generally contains the same DNA. A few exceptions include red blood cells, which contain no DNA in their mature state, and some immune system cells that rearrange their DNA while producing antibodies. In general, however, the genes that determine whether you have green eyes, brown hair, and how fast you metabolize food are the same in the cells in your eyes and your liver, even though these organs function quite differently. If each cell has the same DNA, how is it that cells or organs are different? Why do cells in the eye differ so dramatically from cells in the liver? Whereas each cell shares the same genome and DNA sequence, each cell does not turn on, or express, the same set of genes. Each cell type needs a different set of proteins to perform its function. Therefore, only a small subset of proteins is expressed in a cell. For the proteins to be expressed, the DNA must be transcribed into RNA and the RNA must be translated into protein. In a given cell type, not all genes encoded in the DNA are transcribed into RNA or translated into protein because specific cells in our body have specific functions. Specialized proteins that make up the eye (iris, lens, and cornea) are only expressed in the eye, whereas the specialized proteins in the heart (pacemaker cells, heart muscle, and valves) are only expressed in the heart. At any given time, only a subset of all of the genes encoded by our DNA are expressed and translated into proteins. The expression of specific genes is a highly regulated process with many levels and stages of control. This complexity ensures the proper expression in the proper cell at the proper time. |
In biology, what is required for ecosystems to survive? | minerals | helium | space | energy | In biology, energy is required for ecosystems to survive, as all living organisms need energy. Within an organism, energy is needed for growth and development of a biological cell or an organelle within that cell. Energy is also needed for all biochemical reactions within that cell. Therefore, energy is stored within cells in the chemical bonds of substances such as carbohydrates (including sugars), lipids, and proteins. This energy is released during aerobic respiration. |
Because glucose is a major cellular fuel, starch represents a supply of what? | carbon | oxygen | hydrogen | energy | |
Seed plants that produce seeds in the ovaries of their flowers are known as what? | spores | conifers | gymnosperms | angiosperms | Angiosperms are seed plants that produce seeds in the ovaries of flowers. Today, they are by far the most diverse type of seed plants. In fact, the vast majority of all modern plants are angiosperms. There are hundreds of thousands of species of them. The apple tree in Figure below is an example of a common angiosperm. |
Which blood vessels is oxygen transferred through? | veins | cilia | arteries | capillaries | Of the 23 pairs of human chromosomes, 22 pairs are autosomes (numbers 1–22 in Figure above ). Autosomes are chromosomes that contain genes for characteristics that are unrelated to sex. These chromosomes are the same in males and females. The great majority of human genes are located on autosomes. At the link below, you can click on any human chromosome to see which traits its genes control. http://www. ornl. gov/sci/techresources/Human_Genome/posters/chromosome/chooser. shtml. |
What small biological structures make up all living things, including the human body? | lipids | proteins | scales | cells | Cells make up all living things, including your own body. This picture shows a typical group of cells. But not all cells look alike. Cells can differ in shape and sizes. And the different shapes usually means different functions. |
How does carbon dioxide chemically weather rocks? | by creating heat | by creating proteins | by creating water | by creating acids | Carbon dioxide chemically weathers rock by creating acids. |
What is the interaction of waves with other waves called? | wave dancing | wave mixing | wave induction | wave interference | When two or more waves meet, they interact with each other. The interaction of waves with other waves is called wave interference . Wave interference may occur when two waves that are traveling in opposite directions meet. The two waves pass through each other, and this affects their amplitude. Amplitude is the maximum distance the particles of the medium move from their resting positions when a wave passes through. How amplitude is affected by wave interference depends on the type of interference. Interference can be constructive or destructive. |
What kinds of rocks can change and become new types of rocks? | sedimentary rocks | igneous rocks | metamorphic rocks | any types of rocks | Any type of rock can change and become a new type of rock. Magma can cool and crystallize. Existing rocks can be weathered and eroded to form sediments. Rock can change by heat or pressure deep in Earth's crust. There are three main processes that can change rock:. |
What type of earthquake has a shallow focus because the plates meet near the surface? | tectonic | gas giant | divergent boundary | transform fault | Transform fault earthquakes have shallow focus because the plates meet near the surface. |
What causes waves to bring sand up onto the beach during summers? | low sand density | no energy | high energy | low energy | Waves also move sand from the beaches on shore to bars of sand offshore as the seasons change. In the summer, waves have lower energy so they bring sand up onto the beach. In the winter, higher energy waves bring the sand back offshore. |
What kind of bases completely dissociate in water, releasing all hydroxide anions into the solution? | whole | unusual | weak | strong | Strong bases completely dissociate in water, releasing all hydroxide anions into the solution. The most common strong bases are soluble metal hydroxides. Weak bases partially deprotonate water to form small amounts of hydroxide and the protonated base. |
What model of the atom features an electron orbiting a nucleus, forming a closed-current loop and producing a magnetic field with a north pole and a south pole?. | gravitational model | hydrogen model | solar model | planetary model | Figure 22.13 (a) In the planetary model of the atom, an electron orbits a nucleus, forming a closed-current loop and producing a magnetic field with a north pole and a south pole. (b) Electrons have spin and can be crudely pictured as rotating charge, forming a current that produces a magnetic field with a north pole and a south pole. Neither the planetary model nor the image of a spinning electron is completely consistent with modern physics. However, they do provide a useful way of understanding phenomena. |
Nearly all apicomplexans are parasites of what? | fungi | stars | plants | animals | |
What is the term for sheets of cells that form a boundary between a mass of cells and a cavity or space? | ganglion | mucus | myelin | epithelia | Tight junctions are common at epithelia, which are sheets of cells that form a boundary between a mass of cells and a cavity or space (a lumen ). The membranes of these cells join together, forming a virtually impermeable barrier to fluid. Tight junctions essentially seal adjacent epithelial cells in a narrow layer just beneath their apical surface, which is the portion of the cell exposed to the lumen. The rest of the cell surface is known as the basolateral surface. Tight junctions prevent integral membrane proteins from moving between the apical and basolateral surface, maintaining the properties of those distinct surfaces. For example, receptor-mediated endocytosis occurs at the apical surface and exocytosis at the basolateral surface. |
What does a cell need to transform into a cancerous cell? | adaptations | microbes | parasites | mutations | Typically, a series of several mutations that constitutively activate oncogenes and inactivate tumor suppressor genes is required to transform a normal cell into a cancer cell ( Figure below ). Cells have developed a number of control mechanisms to overcome mutations in proto-oncogenes. Therefore, a cell needs multiple mutations to transform into a cancerous cell. A mutation in one proto-oncogene would not cause cancer, as the effects of the mutation would be masked by the normal control of the cell cycle and the actions of tumor suppressor genes. Similarly, a mutation in one tumor suppressor gene would not cause cancer either, due to the presence of many "backup" genes that duplicate its functions. It is only when enough proto-oncogenes have mutated into oncogenes and enough tumor suppressor genes have been deactivated that the cancerous transformation can begin. Signals for cell growth overwhelm the signals for growth regulation, and the cell quickly spirals out of control. Often, because many of these genes regulate the processes that prevent most damage to the genes themselves, DNA damage accumulates as one ages. |
Circular water waves decrease in what property as they move away from where a rock is dropped? | mass | voltage | frequency | amplitude | 16.11 Energy in Waves: Intensity 17. Two identical waves undergo pure constructive interference. Is the resultant intensity twice that of the individual waves? Explain your answer. Circular water waves decrease in amplitude as they move away from where a rock is dropped. Explain why. |
What property of certain states of matter can be given in units of millimeters of mercury? | velocity | solvency | gravity | pressure | Pressure is given in units of millimeters of mercury. We can either convert this to atmospheres or use the value of the ideal gas constant that includes the mmHg unit. We will take the second option. Substituting into the ideal gas law,. |
Loss of energy is the reason that what typically has few levels? | video games | humans | the atmosphere | food chain | At each level of a food chain, a lot of energy is lost. Only about ten percent of the energy passes to the next level. Where does that energy go? Some energy is given off as heat. Some energy goes into animal wastes. Energy also goes into growing things that another consumer can't eat, like fur. It's because so much energy is lost that most food chains have just a few levels. There’s not enough energy left for higher levels. |
Root-like projections anchor adults of what colony-dwelling animals to solid surfaces such as rocks and reefs? | molluscs | anemones | corals | sponges | Sponges come in a variety of shapes and sizes. For example, they may be shaped like tubes, fans, cones, or just blobs. They range in diameter from about a centimeter (0.4 inches) to over a meter (3.3 feet). Many species live in colonies that may be quite large. Adult sponges are sessile. This means they are unable to move from place to place. Root-like projections anchor them to solid surfaces such as rocks and reefs. |
We divide up the earth's seas into five what, which are really all interconnected? | ecosystems | lakes | continents | oceans | People divide up the seas into five oceans. But they are really all interconnected. Even so, they are all very different. This ocean is near a shore and is obviously in a cold region. It appears to be a good habitat for whales! No matter what, the oceans have a huge influence on the planet, locally and as a whole. |
Regulated by guard cells, stomata allow what to enter and exit the plant? | nutrients | molecules | fluid | gases | Chapter 30 1 Figure 30.7 A and B. The cortex, pith, and epidermis are made of parenchyma cells. 3 Figure 30.34 B. 4 C 6 C 8 A 10 B 12 A 14 B 16 C 18 B 20 D 22 C 24 C 26 C 27 Lawn grasses and other monocots have an intercalary meristem, which is a region of meristematic tissue at the base of the leaf blade. This is beneficial to the plant because it can continue to grow even when the tip of the plant is removed by grazing or mowing. 29 Stomata allow gases to enter and exit the plant. Guard cells regulate the opening and closing of stomata. If these cells did not function correctly, a plant could not get the carbon dioxide needed for photosynthesis, nor could it release the oxygen produced by photosynthesis. 31 In woody plants, the cork cambium is the outermost lateral meristem; it produces new cells towards the interior, which enables the plant to increase in girth. The cork cambium also produces cork cells towards the exterior, which protect the plant from physical damage while reducing water loss. 33 Annual rings can also indicate the climate conditions that prevailed during each growing season. 35 A tap root system. |
The rising and sinking of these can cause precipitation? | temporary air currents | underwater currents | circular air currents | global air currents | Global air currents affect precipitation. How they affect it varies with latitude ( Figure below ). Where air rises, it cools and there is precipitation. Where air sinks, it warms and causes evaporation. These patterns are part of the global wind belts. |
Where does evidence that magnetic reversals occur come from? | air | snow | Volcanoes | rocks on ocean floor | Scientists don’t know for certain why magnetic reversals occur, but there is hard evidence that they have for hundreds of millions of years. The evidence comes from rocks on the ocean floor. Look at Figure below . They show the same ridge on the ocean floor during different periods of time. |
What is used to measure air pressure? | thermometer | metrometer | indicator | barometer | |
As altitude rises, what happens to the temperature in the thermosphere? | temperature decreases | oxygen increases | oxygen decreases | temperature increases | Temperature increases with altitude in the thermosphere. Surprisingly, it may be higher than 1000° C (1800° F) near the top of this layer! The Sun’s energy there is very strong. The molecules absorb the Sun’s energy and are heated up. But there are so few gas molecules that the air still feels very cold. Molecules in the thermosphere gain or lose electrons. They then become charged particles called ions. |
How many stomach compartments do ruminants have? | seven | five | two | four | To help digest the large amount of plant material, the stomach of the ruminants is a multi-chambered organ, as illustrated in Figure 34.8. The four compartments of the stomach are called the rumen, reticulum, omasum, and abomasum. These chambers contain many microbes that break down cellulose and ferment ingested food. The abomasum is the “true” stomach and is the equivalent of the monogastric stomach chamber where gastric juices are secreted. The four-compartment gastric chamber provides larger space and the microbial support necessary to digest plant material in ruminants. The fermentation process produces large amounts of gas in the stomach chamber, which must be eliminated. As in other animals, the small intestine plays an important role in nutrient absorption, and the large intestine helps in the elimination of waste. |
Seismic waves show that the inner core of the earth is solid while the outer core is what? | silicon | gas | lava | liquid | The dense, iron core forms the center of the Earth. Scientists know that the core is metal from studying metallic meteorites and the Earth’s density. Seismic waves show that the outer core is liquid, while the inner core is solid. Movement within Earth's outer liquid iron core creates Earth’s magnetic field. These convection currents form in the outer core because the base of the outer core is heated by the even hotter inner core. |
What do ions of the same charge do? | discard each other | merge | attract each other | repel each other | Ions are highly reactive, especially as gases. They usually react with ions of opposite charge to form neutral compounds. For example, positive sodium ions and negative chloride ions react to form the neutral compound sodium chloride, commonly known as table salt. This occurs because oppositely charged ions attract each other. Ions with the same charge, on the other hand, repel each other. Ions are also deflected by a magnetic field, as you saw in the opening image of the northern lights. |
Integral proteins penetrate the hydrophobic interior of the what? | carbon bilayer | metabolism bilayer | skin bilayer | lipid bilayer | |
The thermal properties of what substance largely contribute to the temperature climate of europe? | clouds | lava | soil | water | mass, water should be a gas at room temperature (20°C), but the strong intermolecular interactions in liquid water greatly increase its boiling point. Hydrogen bonding also produces the relatively open molecular arrangement found in ice, which causes ice to be less dense than water. Because ice floats on the surface of water, it creates an insulating layer that allows aquatic organisms to survive during cold winter months. These same strong intermolecular hydrogen-bonding interactions are also responsible for the high heat capacity of water and its high heat of fusion. A great deal of energy must be removed from water for it to freeze. Consequently, as noted in Chapter 5 "Energy Changes in Chemical Reactions", large bodies of water act as “thermal buffers” that have a stabilizing effect on the climate of adjacent land areas. Perhaps the most striking example of this effect is the fact that humans can live comfortably at very high latitudes. For example, palm trees grow in southern England at the same latitude (51°N) as the southern end of frigid Hudson Bay and northern Newfoundland in North America, areas known more for their moose populations than for their tropical vegetation. Warm water from the Gulf Stream current in the Atlantic Ocean flows clockwise from the tropical climate at the equator past the eastern coast of the United States and then turns toward England, where heat stored in the water is released. The temperate climate of Europe is largely attributable to the thermal properties of water. |
Our sun is on the main sequence, like most stars, and it is classified by what colorful name? | red dwarf | white dwarf | blue dwarf | yellow dwarf | We have a main sequence star nearby. Our Sun is on the main sequence, classified as a yellow dwarf. Our Sun has been a main sequence star for about 5 billion years. As a medium-sized star, it will continue to shine for about 5 billion more years. Most stars are on the main sequence. |
Stirring, surface area, and temperature affect the rate at which what occurs? | solute fragments | concentration dissolves | solute freezes | solute dissolves | When you add sugar to a cold drink, you may stir it to help the sugar dissolve. If you don’t stir, the sugar may eventually dissolve, but it will take much longer. Stirring is one of several factors that affect how fast a solute dissolves in a solvent. Temperature is another factor. A solid solute dissolves faster at a higher temperature. For example, sugar dissolves faster in hot tea than in ice tea. A third factor that affects the rate of dissolving is the surface area of the solute. For example, if you put granulated sugar in a glass of ice tea, it will dissolve more quickly than the same amount of sugar in a cube. That’s because granulated sugar has much more surface area than a cube of sugar. You can see videos of all three factors at these URLs:. |
What process of gradual change is the source of diversity of life on earth? | development | variation | creation | evolution | The Diversity of Life The fact that biology, as a science, has such a broad scope has to do with the tremendous diversity of life on earth. The source of this diversity is evolution, the process of gradual change during which new species arise from older species. Evolutionary biologists study the evolution of living things in everything from the microscopic world to ecosystems. The evolution of various life forms on Earth can be summarized in a phylogenetic tree (Figure 1.17). A phylogenetic tree is a diagram showing the evolutionary relationships among biological species based on similarities and differences in genetic or physical traits or both. A phylogenetic tree is composed of nodes and branches. The internal nodes represent ancestors and are points in evolution when, based on scientific evidence, an ancestor is thought to have diverged to form two new species. The length of each branch is proportional to the time elapsed since the split. |
Shivering helps the body return to a stable what? | mood | pH level | weight | temperature | These people may be having fun in the icy water, but their bodies are struggling to react to the cold. For example, they may begin to shiver. Shivering helps the body return to a stable temperature. The body is always working to achieve stability, or homeostasis. |
What term is used to describe a solution in which water is the solvent? | sediment solution | liquids solution | hydro solution | aqueous solution | Solutions We have previously defined solutions as homogeneous mixtures, meaning that the composition of the mixture (and therefore its properties) is uniform throughout its entire volume. Solutions occur frequently in nature and have also been implemented in many forms of manmade technology. We will explore a more thorough treatment of solution properties in the chapter on solutions and colloids, but here we will introduce some of the basic properties of solutions. The relative amount of a given solution component is known as its concentration. Often, though not always, a solution contains one component with a concentration that is significantly greater than that of all other components. This component is called the solvent and may be viewed as the medium in which the other components are dispersed, or dissolved. Solutions in which water is the solvent are, of course, very common on our planet. A solution in which water is the solvent is called an aqueous solution. A solute is a component of a solution that is typically present at a much lower concentration than the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration). Concentrations may be quantitatively assessed using a wide variety of measurement units, each convenient for particular applications. Molarity (M) is a useful concentration unit for many applications in chemistry. Molarity is defined as the number of moles of solute in exactly 1 liter (1 L) of the solution: M = mol solute L solution. |
What is prosopagnosia? | time blindness | way blindness | lack of memory | face blindness | Brain: Prosopagnosia The failures of sensory perception can be unusual and debilitating. A particular sensory deficit that inhibits an important social function of humans is prosopagnosia, or face blindness. The word comes from the Greek words prosopa, that means “faces,” and agnosia, that means “not knowing. ” Some people may feel that they cannot recognize people easily by their faces. However, a person with prosopagnosia cannot recognize the most recognizable people in their respective cultures. They would not recognize the face of a celebrity, an important historical figure, or even a family member like their mother. They may not even recognize their own face. Prosopagnosia can be caused by trauma to the brain, or it can be present from birth. The exact cause of proposagnosia and the reason that it happens to some people is unclear. A study of the brains of people born with the deficit found that a specific region of the brain, the anterior fusiform gyrus of the temporal lobe, is often underdeveloped. This region of the brain is concerned with the recognition of visual stimuli and its possible association with memories. Though the evidence is not yet definitive, this region is likely to be where facial recognition occurs. Though this can be a devastating condition, people who suffer from it can get by—often by using other cues to recognize the people they see. Often, the sound of a person’s voice, or the presence of unique cues such as distinct facial features (a mole, for example) or hair color can help the sufferer recognize a familiar person. In the video on prosopagnosia provided in this section, a woman is shown having trouble recognizing celebrities, family members, and herself. In some situations, she can use other cues to help her recognize faces. |
Fungi are unique in having cell walls made of what? | lectin | prokaryotic | Protein | chitin | Fungi are a kingdom in the domain Eukarya that includes molds, mushrooms, and yeasts. Most fungi are multicellular. They are unique in having cell walls made of chitin. |
What is the largest body in the solar system? | planet | earth | asteroids | sun | Our Sun is a star. This star provides light and heat and supports almost all life on Earth. The Sun is the center of the solar system. It is by far the largest part of the solar system. Added together, all of the planets make up just 0.2 percent of the solar system's mass. The Sun makes up the remaining 99.8 percent of all the mass in the solar system ( Figure below )!. |
Which part of an earthquake is in the ground where the ground breaks? | the fault | the epicenter | the tectonic plate | the focus | The focus of an earthquake is in the ground where the ground breaks. The epicenter is the point at the surface just above the focus. |
What substances contained in lemons, vinegar, and sour candies have a sour taste? | lactose | proteins | fats | acids | Acids have a sour taste. Lemons, vinegar, and sour candies all contain acids. |
Many microorganisms are single celled and use what for perception and movement? | chloroplasts | nucleus | mitochondria | organelles | Chapter 12 1 MRI uses the relative amount of water in tissue to distinguish different areas, so gray and white matter in the nervous system can be seen clearly in these images. 3 Neurons enable thought, perception, and movement. Plants do not move, so they do not need this type of tissue. Microorganisms are too small to have a nervous system. Many are single-celled, and therefore have organelles for perception and movement. 5 Sodium is moving into the cell because of the immense concentration gradient, whereas potassium is moving out because of the depolarization that sodium causes. However, they both move down their respective gradients, toward equilibrium. 7 A second signal from a separate presynaptic neuron can arrive slightly later, as long as it arrives before the first one dies off, or dissipates. 9 C 11 D 13 B 15 B 17 A 19 C 21 C 23 A 25 B 27 D 29 B 31 D 33 A 34 Running on a treadmill involves contraction of the skeletal muscles in the legs, increase in contraction of the cardiac muscle of the heart, and the production and secretion of sweat in the skin to stay cool. 36 The disease would target oligodendrocytes. In the CNS, oligodendrocytes provide the myelin for axons. 38 Afferent means “toward,” as in sensory information traveling from the periphery into the CNS. Efferent means “away from,” as in motor commands that travel from the brain down the spinal cord and out into the periphery. 40 The cell membrane must reach threshold before voltage-gated Na+ channels open. If threshold is not reached, those channels do not open, and the depolarizing phase of the action potential does not occur, the cell membrane will just go back to its resting state. 42 EPSP1 = +5 mV, EPSP2 = +7 mV, EPSP 3 = +10 mV, IPSP1 = -4 mV, IPSP2 = -3 mV. 5 + 7 + 10 – 4 – 3 = +15 mV. |
Because it produces oxygen, what plant process was necessary for the evolution of animals? | reproduction | germination | death | photosynthesis | Eventually plants evolved. Plants produce oxygen as a product of photosynthesis. Oxygen spread around the planet about 2.5 billion years ago. Many organisms died off because they could not handle the oxygen. But this development was extremely important for other life. Animals need oxygen to breathe. If photosynthesis had not evolved there would be no animals. |
What category of animals in the vertebrate group has a relatively small brain but highly developed sense organs? | primates | mammals | arthropods | fish | Fish have a nervous system with a brain. Fish brains are small compared with the brains of other vertebrates. However, they are large and complex compared with the brains of invertebrates. Fish also have highly developed sense organs. They include organs to see, hear, feel, smell, and taste. |
What distinguishing feature predates the branching of mammals from other vertebrates? | teeth | adaptation | eggs | backbone | |
The simplest way to define a base is which kind of compound that produces hydroxide ions when dissolved in water? | covalent | magnetic | solvent | ionic | The simplest way to define a base is an ionic compound that produces hydroxide ions when dissolved in water. One of the most commonly used bases is sodium hydroxide, illustrated below. |
What is the term for behaviors that are closely controlled by genes with little or no environmental influence? | learned behavior | observational behaviors | reflex behaviors | innate behaviors | Behaviors that are closely controlled by genes with little or no environmental influence are called innate behaviors . These are behaviors that occur naturally in all members of a species whenever they are exposed to a certain stimulus. Innate behaviors do not have to be learned or practiced. They are also called instinctive behaviors. An instinct is the ability of an animal to perform a behavior the first time it is exposed to the proper stimulus. For example, a dog will drool the first time—and every time—it is exposed to food. |
In the forward reaction, hydrogen and iodine combine to form what? | iodinic hydrogen | hydrogen ionicide | ionic hydrogen | hydrogen iodide | In the forward reaction, hydrogen and iodine combine to form hydrogen iodide. In the reverse reaction, hydrogen iodide decomposes back into hydrogen and iodine. The two reactions can be combined into one equation by the use of a double arrow. |
Catalysts can greatly increase the rates of chemical what? | effects | photosynthesis | decay | reactions | and procaine. Not only do catalysts greatly increase the rates of reactions, but in some cases such as in petroleum refining, they also control which products are formed. The acceleration of a reaction by a catalyst is called catalysis. |
Ecology, botany, and zoology are what type of science? | physical sciences | psychological sciences | chemistry | life science | Life is complex and living things are incredibly diverse. Therefore, life science is divided into many fields, such as ecology, botany, and zoology. |
How do we describe chemical reactions? | atomic numbers | balanced reactions | equilibrium | chemical equations | Chemical reactions are described using chemical equations. |
Represented in equations by the letter "g", what pulls objects down to the earth's surface? | light | energy | motion | gravity | Gravity near the Earth pulls an object downwards toward the surface of the Earth with an acceleration of . In the absence of air resistance, all objects will fall with the same acceleration. The letter is used as the symbol for the acceleration of gravity. When talking about an object's acceleration, whether it is due to gravity or not, the acceleration of gravity is sometimes used as a unit of measurement where . So an object accelerating at 2g's is accelerating at or. |
The similarity in biochemical compounds between living things provides evidence for the evolution of species from what? | rare tribes | recent ancestors | varied ancestors | common ancestors | Biochemical compounds are carbon-based compounds that are found in living things. The similarity in biochemical compounds between living things provides evidence for the evolution of species from common ancestors. |
The only invertebrates than can fly belong to what broad group, which is highly successful? | bats | spiders | birds | insects | Insects are the only invertebrates than can fly. Flight is the main reason for their success. |
The dna is wound around proteins called what? | pepsins | leptons | nucleotides | histones | Chapter 9 1 Figure 9.10 Ligase, as this enzyme joins together Okazaki fragments. 2 A 4 B 6 A 8 C 10 D 12 The DNA is wound around proteins called histones. The histones then stack together in a compact form that creates a fiber that is 30-nm thick. The fiber is further coiled for greater compactness. During metaphase of mitosis, the chromosome is at its most compact to facilitate chromosome movement. During interphase, there are denser areas of chromatin, called heterochromatin, that contain DNA that is not expressed, and less dense euchromatin that contains DNA that is expressed. 14 Telomerase has an inbuilt RNA template. |
What part of an animal helps to prevent water loss and gives support and protection? | backbone | membrane | cuticle | exoskeleton | The arthropod exoskeleton consists of several layers of cuticle. The exoskeleton prevents water loss and gives support and protection. It also acts as a counterforce for the contraction of muscles. The exoskeleton doesn’t grow as the animal grows. Therefore, it must be shed and replaced with a new one periodically through life. This is called molting . |
Protozoa are generally difficult to identify due to what? | their formation shape | their hidden shape | their resting shape | their varied shape | 22.10 Protozoa As heterotrophs, protozoa scavenge materials from their surroundings. Others are predators which actively hunt or ambush small organisms such as bacteria and other protozoa for a source of nutrition. Protozoa can be parasitic as well; they may live inside larger organisms, like humans. Most protozoa live as single cells, although a few form colonies. Protozoa are generally difficult to identify due to their varied shape. They may appear as jelly-like blobs, spherical sunbursts, or a flattened leaf. Tiny blood parasites may be only 2 μm long. On the other hand, shell-covered marine may be 5 cm or more in diameter. Furthermore, different protozoans have their own complex life cycles. The complexity has led certain organisms to be mistakenly classified for other species. Nevertheless, protozoa can move, and so, they are classified based on their methods of locomotion. Characteristics of Protozoa : • About 30,000 species known • About 10,000 species are pathogenic, including some of the worst human diseases • heterotrophic • highly variable in form and life cycle. |
Where does digestion begin? | oral cavity | spicule cavity | excretory system | gastrovascular cavity | |
What basic units are neither created nor destroyed during a chemical change, but are instead rearranged? | Electrons | particles | molecules | atoms | Atoms are neither created nor destroyed during a chemical change, but are instead rearranged to yield. |
Which members of the food chain break down remains of plants and other organisms when they die? | fluxes | nematodes | Respiration | decomposers | When plants and other organisms die, decomposers break down their remains. In the process, they release nitrogen in the form of ammonium ions. Nitrifying bacteria change the ammonium ions into nitrates. Some of the nitrates are used by plants. Some are changed back to nitrogen gas by denitrifying bacteria. |
Concentration is the removal of solvent, which increases the concentration of what? | Water | vapor | sodium | solute | Often, a worker will need to change the concentration of a solution by changing the amount of solvent. Dilution is the addition of solvent, which decreases the concentration of the solute in the solution. Concentration is the removal of solvent, which increases the concentration of the solute in the solution. (Do not confuse the two uses of the word concentration here!) In both dilution and concentration, the amount of solute stays the same. This gives us a way to calculate what the new solution volume must be for the desired concentration of solute. From the definition of molarity,. |
What type of coal deposits are the most extensive ever formed? | jurassic | precambrian | mesozoic | carboniferous | |
What is the term for the skeletal structure of the head that supports the face and protects the brain? | thorax | ribcage | pelvis | cranium (skull) | 7.2 | The Skull By the end of this section, you will be able to: • List and identify the bones of the brain case and face • Locate the major suture lines of the skull and name the bones associated with each • Locate and define the boundaries of the anterior, middle, and posterior cranial fossae, the temporal fossa, and infratemporal fossa • Define the paranasal sinuses and identify the location of each • Name the bones that make up the walls of the orbit and identify the openings associated with the orbit • Identify the bones and structures that form the nasal septum and nasal conchae, and locate the hyoid bone • Identify the bony openings of the skull The cranium (skull) is the skeletal structure of the head that supports the face and protects the brain. It is subdivided into the facial bones and the brain case, or cranial vault (Figure 7.3). The facial bones underlie the facial structures, form the nasal cavity, enclose the eyeballs, and support the teeth of the upper and lower jaws. The rounded brain case surrounds and protects the brain and houses the middle and inner ear structures. In the adult, the skull consists of 22 individual bones, 21 of which are immobile and united into a single unit. The 22nd bone is the mandible (lower jaw), which is the only moveable bone of the skull. |
What is it called when organisms with traits that better enable them to adapt to their environment tend to survive and reproduce in greater numbers? | evolution | natural distribution | adaptation | natural selection | New species develop naturally through the process of natural selection . Due to natural selection, organisms with traits that better enable them to adapt to their environment will tend to survive and reproduce in greater numbers. Natural selection causes beneficial heritable traits to become more common in a population and unfavorable heritable traits to become less common. For example, a giraffe’s neck is beneficial because it allows the giraffe to reach leaves high in trees. Natural selection caused this beneficial trait to become more common than short necks. |
A crow that becomes used to a scarecrow and lands on it is an example of what? | dissociation | assimilation | adaptation | habituation | Another example of habituation is shown below ( Figure below ). Crows and most other birds are usually afraid of people. They avoid coming close to people, or they fly away when people come near them. The crows landing on this scarecrow have become used to a “human” in this place. They have learned that the scarecrow poses no danger. They are no longer afraid to come close. They have become habituated to the scarecrow. |
What term is used to describe the sequence of elementary steps that together comprise an entire chemical reaction? | potassium mechanism | source mechanism | elemental mechanism | reaction mechanism | In this equation, the letters A and B represent the reactants that begin the reaction, and the letter C represents the product that is synthesized in the reaction. The arrow shows the direction in which the reaction occurs. |
Structurally, diplomonads have two equal-sized what and multiple flagella? | electrons | atoms | neutrons | nuclei | |
What is the term for the affected factor in an experiment? | independent variable | multiple variable | stable variable | dependent variable | Test the hypothesis. Make predictions based on the hypothesis and then determine if they are correct. This may involve carrying out an experiment. An experiment is a controlled scientific test that often takes place in a lab. It investigates the effects of one factor, called the independent variable , on another factor, called the dependent variable . Experimental controls are other factors that might affect the dependent variable. Controls are kept constant so they will not affect the results of the experiment. |
Furthermore, most of the proteins within membranes have both hydrophobic and which other regions? | cytosolic | atmospheric | lymphatic | hydrophilic | |
What are proteins that increase the rate of biochemical reactions? | amino acids | metabolites | hormones | enzymes | Enzymes are proteins that increase the rate of biochemical reactions. Enzymes aren’t changed or used up in the reactions, so they can be used to speed up the same reaction over and over again. Enzymes are highly specific for certain chemical reactions, so they are very effective. A reaction that would take years to occur without its enzyme might occur in a split second with the enzyme. |
What process enables all living things to maintain a constant internal environment? | ketosis | peristalsis | consciousness | homeostasis | All living things are able to maintain a constant internal environment through homeostasis. |
Which hormone is secreted by the pancreas in a human body? | estrogen | growth hormone | progesterone | insulin | The pancreas is a large gland located near the stomach. Hormones secreted by the pancreas include insulin. Insulin helps cells absorb glucose from the blood. It also stimulates the liver to take up and store excess glucose. |
What are the gas giants mostly made of . | hydrogen and carbon | calcium and helium | nitrogen and helium | hydrogen and helium | The gas giants are mostly made of hydrogen and helium. These are the same elements that make up most of the Sun. Astronomers think that most of the nebula was hydrogen and helium. The inner planets lost these very light gases. Their gravity was too low to keep them and they floated away into space. The Sun and the outer planets had enough gravity to keep the hydrogen and helium. |
Static friction acts on objects when they are resting on what? | a pool of water | a single point | their laurels | a surface | Static friction acts on objects when they are resting on a surface. For example, if you are hiking in the woods, there is static friction between your shoes and the trail each time you put down your foot (see Figure below ). Without this static friction, your feet would slip out from under you, making it difficult to walk. In fact, that’s exactly what happens if you try to walk on ice. That’s because ice is very slippery and offers very little friction. |
The ammonium ion is what type of acid? | oxidized - lowry | normal -lowry | kaon - lowry | brønsted-lowry | We can also consider the reverse reaction in the above equation. In that reaction, the ammonium ion donates a proton to the hydroxide ion. The ammonium ion is a Brønsted-Lowry acid, while the hydroxide ion is a Brønsted-Lowry base. Most Brønsted-Lowry acid-base reactions can be analyzed in this way. There is one acid and one base as reactants, and one acid and one base as products. |
Loss of muscle mass due to breakdown of structural proteins is known as what? | exhaustion | distrophy | mutation | atrophy | 10.6 Exercise and Muscle Performance Hypertrophy is an increase in muscle mass due to the addition of structural proteins. The opposite of hypertrophy is atrophy, the loss of muscle mass due to the breakdown of structural proteins. Endurance exercise causes an increase in cellular. |
Which of these is last if ordered in increasing size: galaxy, solar system, star cluster? | star cluster | none of these | solar system | galaxy | Compared to Earth, the solar system is a big place. Compared to the solar system a star cluster is a big place. But galaxies are bigger—a lot bigger. |
What encloses the genetic material of the virus? | the spindle | mitochondria | nuclei | the capsid | Diagram of a Cytomegalovirus. The capsid encloses the genetic material of the virus. The envelope which surrounds the capsid is typically made from portions of the host cell membranes (phospholipids and proteins). Not all viruses have a viral envelope. |
Plant-like protists are called what? | yeasts | bacterium | sponge | algae | Plant-like protists are called algae. They include single-celled diatoms and multicellular seaweed. Like plants, they contain chlorophyll and make food by photosynthesis. Types of algae include red and green algae, euglenids, and dinoflagellates. |
How do mammals ventilate their lungs? | negative pressure vocalizing | negative combination breathing | negative atmospheric breathing | negative pressure breathing | |
Blood vessels blood pumped by the heart flows through a series of vessels known as arteries, arterioles, capillaries, venules, and veins before returning to this? | brain | lungs | feet | heart | CHAPTER REVIEW 20.1 Structure and Function of Blood Vessels Blood pumped by the heart flows through a series of vessels known as arteries, arterioles, capillaries, venules, and veins before returning to the heart. Arteries transport blood away from the heart and branch into smaller vessels, forming arterioles. Arterioles distribute blood to capillary beds, the sites of exchange with the body tissues. Capillaries lead back to small vessels known as venules that flow into the larger veins and eventually back to the heart. The arterial system is a relatively high-pressure system, so arteries have thick walls that appear round in cross section. The venous system is a lower-pressure system, containing veins that have larger lumens and thinner walls. They often appear flattened. Arteries, arterioles, venules, and veins are composed of three tunics known as the tunica intima, tunica media, and tunica externa. Capillaries have only a tunica intima layer. The tunica intima is a thin layer composed of a simple squamous epithelium known as endothelium and a small amount of connective tissue. The tunica media is a thicker area composed of variable amounts of smooth muscle and connective tissue. It is the thickest layer in all but the largest arteries. The tunica externa is primarily a layer of connective tissue, although in veins, it also contains some smooth muscle. Blood flow through vessels can be dramatically influenced by vasoconstriction and vasodilation in their walls. |
What do you call the fragments of cells involved in the clotting process that are suspended in blood plasma? | hemoglobin | hematocrit | ironites | platelets |
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