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Within an organism, the cells that give rise to the next generation are known as germ cells, while those that do not (that is, the cells that die when the organism dies) are known as what cells? | cloning | xylem | neural | somatic | reality versus abstraction. It is organisms, whether single- or multi-cellular, that produce new organisms. As we will discuss in detail when we consider the origins of multicellular organisms, a cell within a multicellular organism normally cannot survive outside the organism nor can it produce a new organism - it depends upon cooperation with the other cells of the organism. In fact, each multicellular organism is an example of a cooperative, highly integrated social system. The cells of a typical multicellular organism are part of a social system in which most cells have given up their ability to reproduce a new organism; their future depends upon the reproductive success of the organism of which they are a part. It is the organism’s success in generating new organisms that underlies evolution’s selective mechanisms. Within the organism, the cells that give rise to the next generation of organism are known as germ cells, those that do not (that is, the cells that die when the organism dies) are known as somatic cells.47 All organisms in the modern world, and for apparently the last ~3.5-3.8 billion years, arise from a pre-existing organism or, in the case of sexually reproducing organisms, from the cooperation of two organisms, an example of social evolution that we will consider in greater detail in Chapter 4. We will also see that breakdowns in such social systems can lead to the death of the organism or the disruption of the social system. Cancer is the most obvious example of an anti-social behavior; in evolutionary terms, it can, initially, be rewarded (more copies of the cancerous cell are produced) but ultimately leads to the extinction of the cancer, and often the death of the organism within which the cancer occurs.48 This is because evolutionary mechanisms are not driven by long term outcomes, but only by immediate ones. Spontaneous generation and the origin of life
The ubiquity of organisms raises obvious questions: how did life start and what led to all these different types of organisms? At one point, people believed that these two questions had a single answer, but we now recognize that they are really two quite distinct questions and their answers involve distinct mechanisms. An early view held by those who thought about such things was that supernatural processes were necessary to produced life in general and human beings in particular. The articulation of the Cell Theory and the Theory of Evolution by Natural Selection, which we will discuss in detail in the next chapter, together with an accumulation of data enables us to conclude quite persuasively that life had a single successful origin, that only natural processes were involved, and that various (again natural) evolutionary processes generated the diversity of life. But how did life itself originate? It used to be widely accepted that various types of organisms, such as flies, frogs, and even mice, could arise spontaneously, from non-living matter.49 Flies, for example, were thought to appear from rotting flesh and mice from wheat. If true, on-going spontaneous generation would have profound implications for our understanding of biological systems. For example,. |
An external opening in the what of amphibians allows wastes and gametes to exit the body? | urethra | anus | oral cavity | cloaca | All amphibians have digestive, excretory, and reproductive systems. All three of these organ systems use a single body cavity, called the cloaca. Wastes enter the cloaca from the digestive and excretory systems. Gametes enter the cloaca from the reproductive system. A single external opening in the cloaca allows the wastes and gametes to exit the body. (Many other four legged vertebrates also have a cloaca. ). |
What kind of scientists measure percentages of sand, silt, and clay? | petro scientists | texture scientists | amount scientists | soil scientists | Soil scientists measure the percentage of sand, silt, and clay in soil. They plot this information on a triangular diagram, with each type of particle at one corner ( Figure below ). |
What hormone affects developent and maturation in animals? | melatonin | insulin | dopamine | thyroid | |
The three types of mammals are characterized by their method of what? | pattern | specializaiton | differentiation | reproduction | There are three types of mammals, characterized by their method of reproduction. All mammals, except for a few, are viviparous , meaning they produce live young instead of laying eggs. The monotremes , however, have birdlike and reptilian characteristics, such as laying eggs and a cloaca. An example of a monotreme is the platypus with its birdlike beak and egg-laying characteristics. The echidnas are the only other monotreme mammals. A second type of mammal, the marsupial mammal, includes kangaroos, wallabies, koalas and possums. These mammals give birth to underdeveloped embryos, which then climb from the birth canal into a pouch on the front of the mother's body, where it feeds and continues to grow. The remainder of mammals, which is the majority of mammals, are placental mammals. These mammals develop in the mother's uterus, receiving nutrients across the placenta. Placental mammals include humans, rabbits, squirrels, whales, elephants, shrews, and armadillos. Dogs and cats, and sheep, cattle and horses are also placental mammals. |
What planet has the most volcanoes? | uranus | Mars | Earth | venus | Venus has more volcanoes than any other planet. There are between 100,000 and one million volcanoes on Venus! Most of the volcanoes are now inactive. There are also a large number of craters. This means that Venus doesn’t have tectonic plates. Plate tectonics on Earth erases features over time. Figure below is an image made using radar data. The volcano is Maat Mons. Lava beds are in the foreground. Scientists think the color of sunlight on Venus is reddish-brown. |
Gene duplications that are able to persist over many generations without causing too much harm to an organism or species can lead to what? | permutations | characteristics | parasites | mutations | |
What keeps earth in orbit around the sun? | momentum | energy | motion | gravity | Why do satellites stay in orbit? Why don't they crash into Earth due to the planet's gravity? Newton’s law of universal gravitation describes what happens. Every object in the universe is attracted to every other object. Gravity makes an apple fall to the ground. Gravity also keeps you from floating away into the sky. Gravity holds the Moon in orbit around Earth. It keeps Earth in orbit around the Sun. |
The work-energy theorem states that the net work on a system equals the change in what type of energy? | residual energy | binary energy | new energy | kinetic energy | How the Work-Energy Theorem Applies Now let us consider what form the work-energy theorem takes when both conservative and nonconservative forces act. We will see that the work done by nonconservative forces equals the change in the mechanical energy of a system. As noted in Kinetic Energy and the Work-Energy Theorem, the work-energy theorem states that the net work on a system equals the change in its kinetic energy, or W net = ΔKE . The net work is the sum of the work by nonconservative forces plus the work by conservative forces. That is,. |
Living organisms release carbon dioxide into the atmosphere by what method? | major respiration | genomic respiration | widespread respiration | cellular respiration | Cellular respiration by living things releases carbon into the atmosphere or ocean as carbon dioxide. |
Excretory organs that conserve what essential substance help terrestrial animals to avoid desiccation? | food | metabolytes | air | water | |
Venus rotates slowly in a direction opposite to the direction of what? | the sun | the Earth's orbit | the orbit of Mars | its orbit | Venus rotates slowly in a direction opposite to the direction of its orbit. |
What is the ph of pure water? | 2 | 5 | 4 | 7 | milk of magnesia, pH = 10.5 2. pure water, pH = 7 3. wine, pH = 3.0. |
The volume of a gas is comprised of about 10% matter. what is the rest? | normal space | open space | instead space | empty space | The volume of a gas contains only about 10% matter, with the rest being empty space. ΔHsub is equal to ΔHvap. |
Heterotrophs is another name for what group? | producers | omnivores | autotrophs | consumers | Consumers are also called heterotrophs. There are several different types of heterotrophs depending on exactly what they consume. They may be herbivores, carnivores, or omnivores. |
What is dna transcribed into after being replicated? | gene | protein | diploid chromosomes | rna | The three general transfers are believed to occur normally in most cells. These describe the normal flow of biological information. DNA is replicated, DNA is transcribed into RNA, and RNA is translated into protein. The three special transfers are known to occur under special conditions, such as with some viruses. The three unknown transfers are not believed to occur. |
What is name of the phenomenon where similar traits evolve independently in species that do not share a common ancestry? | divergent evolution | equation evolution | coalescence evolution | convergent evolution | Figure 22.31 The force on a current-carrying wire in a magnetic field is. |
The flow of water through the sponge is unidirectional, driven by the beating of what? | fin | antennae | cilia | flagella | Sponges are characterized by a feeding system unique among animals. As sponges don't have mouths, they must feed by some other method. Sponges have tiny pores in their outer walls through which water is drawn. Cells in the sponge walls filter food from the water as the water is pumped through the body and out other larger openings. The flow of water through the sponge is unidirectional, driven by the beating of flagella, which line the surface of chambers connected by a series of canals. |
What is the process for developing knowledge called? | creationism | evolution | theory | science | Science is a process for developing knowledge. Change in knowledge about the natural world is expected because there is often room for new observations which may challenge current views. No matter how well one theory explains a set of observations, it is possible that a different theory may explain them just as well or better, or may also encompass a wider range of observations. Scientists are always testing and attempting to improve theories. Scientists know that even if there is no way to gain complete knowledge about something, an increasingly accurate understanding of nature will develop over time. |
Arteries, veins, and capillaries are the three main types of what? | blood pathways | blood shapes | cell structures | blood vessels | |
Amphibians may attract mates with what? | neither | only calls | only scents | calls or scents | Amphibians may attract mates with calls or scents. |
What type of bounded nucleus do protists have? | Ribosomes | Mitochondrion | Endoplasmic reticulum | membrane | |
Which body part is unsuitable for animals living on land? | hands | lungs | feet | gills | |
Which inducer turns on the expression of the lac genes? | galactose | xerophyte | glucose | allolactose | When lactose is available, a lactose metabolite called allolactose binds to the allosteric site on the repressor. This interaction causes a conformational change in the repressor shape and the repressor falls off the operator, allowing RNA polymerase to bind to the promoter and initiate transcription. Allolactose is called an inducer because it turns on, or induces the expression of the lac genes. |
What is the most common type of brain injury? | Contusion | Diffuse Axonal | Anoxic Event | concussion | The most common type of brain injury is a concussion. This is a bruise on the surface of the brain. It may cause temporary symptoms such as headache and confusion. Most concussions heal on their own in a few days or weeks. However, repeated concussions can lead to permanent changes in the brain. More serious brain injuries also often cause permanent brain damage. |
Changing the shape of an elastic material gives it what type of energy? | initial | thermal | practical | potential | Changing the shape of an elastic material gives it potential energy. |
What type of traits are features that are passed from one generation to the next called? | familial traits | generational traits | genetic traits | inherited traits | The theory of evolution by natural selection means that the inherited traits of a population change over time. Inherited traits are features that are passed from one generation to the next. For example, your eye color is an inherited trait. You inherited your eye color from your parents. Inherited traits are different from acquired traits , or traits that organisms develop over a lifetime, such as strong muscles from working out ( Figure below ). |
What is your body made up of? | energy | skin | millions of elements | trillions of cells | According to the cell theory , all living things are made up of cells, which is the structural unit of living organisms, and living cells always come from other living cells. In fact, each living thing begins life as a single cell. Some living things, such as bacteria, remain single-celled. Other living things, including plants and animals, grow and develop into many cells. Your own body is made up of an amazing 100 trillion cells! But even you—like all other living things—began life as a single cell. |
Hemoglobin is responsible for transporting what within our blood? | dioxide | water | nitrogen | oxygen | To predict the relative stabilities of metal complexes with different ligands. One of the most important properties of metallic elements is their ability to act as Lewis acids that form complexes with a variety of Lewis bases. A metal complex consists of a central metal atom or ion that is bonded to one or more ligands (from the Latinligare, meaning “to bind”), which are ions or molecules that contain one or more pairs of electrons that can be shared with the metal. Metal complexes can be neutral, such as Co(NH3)3Cl3; positively charged, such as [Nd(H2O)9]3+; or negatively charged, such as [UF8]4−. Electrically charged metal complexes are sometimes called complex ions. A coordination compound contains one or more metal complexes. Coordination compounds are important for at least three reasons. First, most of the elements in the periodic table are metals, and almost all metals form complexes, so metal complexes are a feature of the chemistry of more than half the elements. Second, many industrial catalysts are metal complexes, and such catalysts are steadily becoming more important as a way to control reactivity. For example, a mixture of a titanium complex and an organometallic compound of aluminum is the catalyst used to produce most of the polyethylene and polypropylene “plastic” items we use every day. Finally, transition-metal complexes are essential in biochemistry. Examples include hemoglobin, an iron complex that transports oxygen in our blood; cytochromes, iron complexes that transfer electrons in our cells; and complexes of Fe, Zn, Cu, and Mo that are crucial components of certain enzymes, the catalysts for all biological reactions. Metal complexes are so important in biology that we consider the topic separately in Section 23.6 "Transition Metals in Biology". |
How do bipedal creatures walk? | on four legs | on twelve legs | on six legs | on two legs | Birds are endothermic tetrapod vertebrates. They are bipedal, which means they walk on two legs. Birds also lay amniotic eggs with hard, calcium carbonate shells. Although birds are the most recent class of vertebrates to evolve, they are now the most numerous vertebrates on Earth. Why have birds been so successful? What traits allowed them to increase and diversify so rapidly? Birds can vary considerably in size, as you can see from the world’s smallest and largest birds, pictured in Figure below . The tiny bee hummingbird is just 5 centimeters (2 inches) long, whereas the ostrich towers over people at a height of 2.7 meters (9 feet). All modern birds have wings, feathers, and beaks. They have a number of other unique traits as well, most of which are adaptations for flight. Flight is used by birds as a means of locomotion in order to find food and mates and to avoid predators. Although not all modern birds can fly, they all evolved from ancestors that could. |
Any sample of matter that has the same physical and chemical properties throughout the sample is called what? | type | element | molecule | substance | Elements and Compounds Any sample of matter that has the same physical and chemical properties throughout the sample is called a substance. There are two types of substances. A substance that cannot be broken down into chemically simpler components is an element. Aluminum, which is used in soda cans, is an element. A substance that can be broken down into chemically simpler components (because it has more than one element) is acompound (Figure 1.2 "The General Steps of the Scientific Method"). Water is a compound composed of the elements hydrogen and oxygen. Today, there are about 118 elements in the known universe. In contrast, scientists have identified tens of millions of different compounds to date. |
What is a measure of both speed and direction of motion? | acceleration | distance | intensity | velocity | Velocity is a measure of both speed and direction of motion. Velocity is a vector, which is a measurement that includes both size and direction. |
What do fish eggs hatch to form? | unfertilized eggs | adolescent fish | tadpoles | fish eggs hatch to form larvae | Almost all fish have sexual reproduction, generally with separate sexes. Most fish are oviparous. Many species reproduce by spawning. Eggs hatch to form larvae, which undergo metamorphosis to become adults. |
Commensalism, mutualism, and parasitism are known as what type of relationships? | various | simple | peculiar | symbiotic | 19.4 Community Ecology Communities include all the different species living in a given area. The variety of these species is referred to as biodiversity. Many organisms have developed defenses against predation and herbivory, including mechanical defenses, warning coloration, and mimicry. Two species cannot exist indefinitely in the same habitat competing directly for the same resources. Species may form symbiotic relationships such as commensalism, mutualism, or parasitism. Community. |
The modern model of the atom, which scientists call the quantum mechanical model, is based on what scientist's work on orbitals? | Newton | Sagan | Bohr | schrödinger | Schrödinger’s work on orbitals is the basis of the modern model of the atom, which scientists call the quantum mechanical model. The modern model is also commonly called the electron cloud model. That’s because each orbital around the nucleus of the atom resembles a fuzzy cloud around the nucleus, like the ones shown in the Figure below for a helium atom. The densest area of the cloud is where the electrons have the greatest chances of being. |
Time, mass, length, and temperature are considered to be what kinds of units? | unitary | support | measurement | base | Base units have independent scales and cannot be described by a combination of any other base units. Examples of base units used in chemistry are length, mass, temperature, and time. |
What does the heat energy affect in the atmosphere? | density and humidity | gravity and precipitation | erosion and condensation | winds and weather | How do the differences in energy striking different latitudes affect Earth? The planet is much warmer at the equator than at the poles. In the atmosphere, the differences in heat energy cause winds and weather. On the surface, the differences cause ocean currents. Can you explain how?. |
What are the taste receptors found as tiny bumps on the tongue called? | hard buds | ear buds | fat buds | taste buds | Taste receptors are found in tiny bumps on the tongue called taste buds (see Figure below ). There are separate taste receptors for sweet, salty, sour, bitter, and meaty tastes. The meaty taste is called umami . You can learn more about taste receptors and the sense of taste by watching the animation at the following link: http://www. bbc. co. uk/science/humanbody/body/factfiles/taste/taste_ani_f5. swf . |
What is the chemical formula for a glucose molecule? | d5 h12 o6 | a5 h12 o6 | H2 C3 NA6 | c6 h12 o6 | The sugar glucose is a covalent compound. When sugar dissolves in water, it forms individual glucose molecules (C 6 H 12 O 6 ). You can see how this happens in the Figure below . Sugar is polar like water, so sugar molecules also have positive and negative ends. Forces of attraction between oppositely charged ends of water and sugar molecules pull individual sugar molecules away from the sugar crystal. Little by little, the sugar molecules are separated from the crystal and surrounded by water. You can watch this happening in the video at the following URL: http://www. youtube. com/watch?v=hydUVGUbyvU. |
In physics, the number of waves that pass a fixed point in a given amount time is referred to as what ? | creation frequency | combination frequency | wave count | wave frequency | Wave speed is related to both wavelength and wave frequency. Wavelength is the distance between two corresponding points on adjacent waves. Wave frequency is the number of waves that pass a fixed point in a given amount of time. This equation shows how the three factors are related:. |
The reactions between alkali metals and water are particularly vigorous and include the rapid production of large quantities of what gas? | carbon | helium | oxygen | hydrogen | All alkali metals are very soft and can be cut easily with a knife. Due to their high reactivity, they must be stored under oil to prevent them from reacting with oxygen or water vapor in the air. The reactions between alkali metals and water are particularly vigorous and include the rapid production of large quantities of hydrogen gas. Alkali metals also react easily with most nonmetals. All of the alkali metals are far too reactive to be found in nature in their pure elemental form. For example, all naturally occurring sodium exists as a compound, such as sodium chloride (table salt). |
Batteries produce voltage through what type of reaction? | thermal | magnetic | radiation | chemical | Chemical cells are found in batteries. They produce voltage by means of chemical reactions. A chemical cell has two electrodes, which are strips made of different materials, such as zinc and carbon (see Figure below ). The electrodes are suspended in an electrolyte. An electrolyte is a substance containing free ions that can carry electric current. The electrolyte may be either a paste, in which case the cell is called a dry cell, or a liquid, in which case the cell is called a wet cell. Flashlight batteries contain dry cells. Car batteries contain wet cells. Animations at the URL below show how batteries work. |
The speed of a particle in what state is directly proportional to the temperature of the system? | liquid | frozen | solid | gas | The speed of a gas particle is directly proportional to the temperature of the system. |
Acne results from a blockage of sebaceous glands by what? | fat | mucous | progesterone | sebum | Chapter 5 1 The epidermis provides protection, the dermis provides support and flexibility, and the hypodermis (fat layer) provides insulation and padding. 3 Figure 5.6 These cells have desmosomes, which give the cells their spiny appearance. 5 D 7 C 9 C 11 D 13 B 15 A 17 C 19 C 21 C 23 B 25 The pigment melanin, produced by melanocytes, is primarily responsible for skin color. Melanin comes in different shades of brown and black. Individuals with darker skin have darker, more abundant melanin, whereas fair-skinned individuals have a lighter shade of skin and less melanin. Exposure to UV irradiation stimulates the melanocytes to produce and secrete more melanin. 27 Eccrine sweat glands are all over the body, especially the forehead and palms of the hand. They release a watery sweat, mixed with some metabolic waste and antibodies. Apocrine glands are associated with hair follicles. They are larger than eccrine sweat glands and lie deeper in the dermis, sometimes even reaching the hypodermis. They release a thicker sweat that is often decomposed by bacteria on the skin, resulting in an unpleasant odor. 29 Sweating cools the body when it becomes warm. When the body temperature rises, such as when exercising on a hot day, the dermal blood vessels dilate, and the sweat glands begin to secrete more sweat. The evaporation of the sweat from the surface of the skin cools the body by dissipating heat. 31 Acne results from a blockage of sebaceous glands by sebum. The blockage causes blackheads to form, which are susceptible to infection. The infected tissue then becomes red and inflamed. Teenagers experience this at high rates because the sebaceous glands become active during puberty. Hormones that are especially active during puberty stimulate the release of sebum, leading in many cases to blockages. |
Just as millions of different words are spelled with our 26-letter english alphabet, millions of different proteins are made with the 20 common what? | enzymes | mutation acids | peptides | amino acids | Just as millions of different words are spelled with our 26-letter English alphabet, millions of different proteins are made with the 20 common amino acids. However, just as the English alphabet can be used to write gibberish, amino acids can be put together in the wrong sequence to produce nonfunctional proteins. Although the correct sequence is ordinarily of utmost importance, it is not always absolutely required. Just as you can sometimes make sense of incorrectly spelled English words, a protein with a small percentage of “incorrect” amino acids may continue to function. However, it rarely functions as well as a protein having the correct sequence. There are also instances in which seemingly minor errors of sequence have disastrous effects. For example, in some people, every molecule of hemoglobin (a protein in the blood that transports oxygen) has a single incorrect amino acid unit out of about 300 (a single valine replaces a glutamic acid). That “minor” error is responsible for sickle cell anemia, an inherited condition that usually is fatal. |
Anaerobic respiration takes place without what? | carbon | nitrogen | movement | oxygen | Aerobic respiration , which takes place in the presence of oxygen, evolved after oxygen was added to Earth’s atmosphere. This type of respiration is useful today because the atmosphere is now 21% oxygen. However, some anaerobic organisms that evolved before the atmosphere contained oxygen have survived to the present. Therefore, anaerobic respiration , which takes place without oxygen, must also have advantages. |
Which other planet in the solar system is the easiest to observe from earth? | Jupiter | Pluto | Mercury | mars | Mars is the easiest planet to observe. As a result, it has been studied more than any other planet besides Earth. People can stand on Earth and observe the planet through a telescope. We have also sent many space probes to Mars. In April 2011, there were three scientific satellites in orbit around Mars. The rover, Opportunity, was still moving around on the surface. No humans have ever set foot on Mars. NASA and the European Space Agency have plans to send people to Mars. The goal is to do it sometime between 2030 and 2040. The expense and danger of these missions are phenomenal. |
What is in the inside of your mouth and nose instead of skin? | cuticle layer | scales | gums | mucous membranes | The mouth and nose are not lined with skin. Instead, they are lined with mucous membranes . Other organs that are exposed to the outside world, including the lungs and stomach, are also lined with mucous membranes. Mucous membranes are not tough like skin, but they have other defenses. |
While matter is recycled, ecosystems need a constant input of what? | light | heating | food | energy | In all biomes, ecosystems need a constant input of energy. Matter, on the other hand, is constantly recycled in ecosystems. |
What is term for the smallest particle of an element that still has the properties of said element? | molecule | proton | nucleus | atom | Atoms are the building blocks of matter. They are the smallest particles of an element that still have the element’s properties. Elements, in turn, are pure substances—such as nickel, hydrogen, and helium—that make up all kinds of matter. All the atoms of a given element are identical in that they have the same number of protons, one of the building blocks of atoms (see below). They are also different from the atoms of all other elements, as atoms of different elements have different number of protons. For an entertaining introduction to atoms by Bill Nye the Science Guy, watch the video at this URL:. |
What is the protein that carries iron that binds with oxygen in red blood cells? | insulin | keratin | potassium | hemoglobin | The trillions of red blood cells in blood plasma carry oxygen. Red blood cells contain hemoglobin , a protein with iron that binds with oxygen. Red blood cells are made in the marrow of long bones, rib bones, the skull, and the vertebrae. These cells survive for about 120 days, and then they are destroyed. Mature red blood cells lack a nucleus and other organelles, allowing for more hemoglobin, and therefore more oxygen to be carried by each cell. |
What branch of science is based on the modern atomic theory, which states that all matter is composed of atoms? | biology | physics | psychology | chemistry | Chemistry is based on the modern atomic theory, which states that all matter is composed of atoms. |
Why do sharks sense low levels of electricity? | to reproduce | to locate mates | to sleep | to locate prey | Fish also have a centralized nervous system with a brain. Fish brains are small compared with the brains of other vertebrates, but they are large and complex compared with the brains of invertebrates. Fish also have highly developed sense organs that allow them to see, hear, feel, smell, and taste. Sharks and some other fish can even sense the very low levels of electricity emitted by other animals. This helps them locate prey. |
What membrane is populated by two types of photosystems that cooperate in the light reactions of photosynthesis? | subcutaneous | choroid | chloroplasts | thylakoid | |
At what point can nutrients enter or exit an ecosystem? | Hottest Point | Largest Population Point | Longest Point | any point | Nutrients can enter or exit an ecosystem at any point and can cycle around the planet. |
B cells and t cells are examples of what type of cells? | skin cells | heart cells | cancer cells | white blood cells | There are two different types of specific immune responses. One type involves B cells. The other type involves T cells. Recall that B cells and T cells are types of white blood cells that are key in the immune response. Whereas the immune system's first and second line of defense are more generalized or non-specific, the immune response is specific. It can be described as a specific response to a specific pathogen, meaning it uses methods to target just one pathogen at a time. These methods involve B and T cells. |
There are three different types of rna. all three types are needed to make what? | Blood | acids | lipids | proteins | There are three different types of RNA. All three types are needed to make proteins. |
Niche and habitat are concepts related to what broader term? | community | population | biome | ecosystem | 7. Compare and contrast the ecosystem concepts of niche and habitat. |
What do opposite charges do to one another? | repel | strengthen | weaken | attract | Opposite charges attract, and like charges repel. |
What is the name for the sinking of the dense, salty seawater in cold climates? | tidal activity | cyclones | jet stream | downwelling | Water becomes more dense when it is colder and when it has more salt. In the North Atlantic Ocean, cold winds chill the water at the surface. Sea ice grows in this cold water, but ice is created from fresh water. The salt is left behind in the seawater. This cold, salty water is very dense, so it sinks to the bottom of the North Atlantic. Downwelling can take place in other places where surface water becomes very dense (see Figure below ). |
When gas particles heat up and gain energy, what do they do? | move slower | go up | stop | move faster | When gas particles heat up and gain energy, they move faster. This increases their collisions with each other and their container, causing greater pressure. |
Ion pumps, the biological machines responsible for the selective transport of metal ions, are complex assemblies of what? | acids | cells | minerals | proteins | Ion Transport The Na+, K+, Mg2+, and Ca2+ ions are important components of intracellular and extracellular fluids. Both Na+ and Ca2+ are found primarily in extracellular fluids, such as blood plasma, whereas K + and Mg2+ are found primarily in intracellular fluids. Substantial inputs of energy are required to establish and maintain these concentration gradients and prevent the system from reaching equilibrium. Thus energy is needed to transport each ion across the cell membrane toward the side with the higher concentration. The biological machines that are responsible for the selective transport of these metal ions are complex assemblies of proteins called ion pumps. Ion pumps recognize and discriminate between metal ions in the same way that crown ethers and cryptands do, with a high affinity for ions of a certain charge and radius. Defects in the ion pumps or their control mechanisms can result in major health problems. For example, cystic fibrosis, the most common inherited disease in the United States, is caused by a defect in the transport system (in this case, chloride ions). Similarly, in many cases, hypertension, or high blood pressure, is thought to be due to defective Na+ uptake and/or excretion. If too much Na+ is absorbed from the diet (or if too little is excreted), water diffuses from tissues into the blood to dilute the solution, thereby decreasing the osmotic pressure in the circulatory system. The increased volume increases the blood pressure, and ruptured arteries called aneurysms can result, often in the brain. Because high blood pressure causes other medical problems as well, it is one of the most important biomedical disorders in modern society. For patients who suffer from hypertension, low-sodium diets that use NaCl substitutes, such as KCl, are often prescribed. Although KCl and NaCl give similar flavors to foods, the K + is not readily taken up by the highly specific Na+-uptake system. This approach to controlling hypertension is controversial, however,. |
Lack of proper food over a period of time can lead to what condition, where the body is not getting enough nutrients to grow and stay healthy? | bulimia | anemia | mortality | malnutrition | Refusing one meal won't stunt your growth. But lack of proper food over a period of time can lead to malnutrition. That means, the body is not getting enough nutrients to grow and stay healthy. Kids who are malnourished may not grow as tall as they would otherwise. |
Two water molecules contain 4 hydrogen atoms and how many oxygen atoms? | 6 | 1 | 4 | 2 | Two water molecules contain 4 hydrogen atoms and 2 oxygen atoms. A mole of water molecules contains 2 moles of hydrogen atoms and 1 mole of oxygen atoms. |
The carrying angle is larger in females to accommodate their what? | cranium | broader shoulders | narrower pelvis | wider pelvis | the ulna and radius bones. The small, rounded area that forms the distal end is the head of the ulna. Projecting from the posterior side of the ulnar head is the styloid process of the ulna, a short bony projection. This serves as an attachment point for a connective tissue structure that unites the distal ends of the ulna and radius. In the anatomical position, with the elbow fully extended and the palms facing forward, the arm and forearm do not form a straight line. Instead, the forearm deviates laterally by 5–15 degrees from the line of the arm. This deviation is called the carrying angle. It allows the forearm and hand to swing freely or to carry an object without hitting the hip. The carrying angle is larger in females to accommodate their wider pelvis. |
Examples of organ systems in a human include the skeletal, nervous, and what? | immune systems | affecting systems | nervous systems | reproductive systems | Organ system : Group of organs that work together to perform a certain function. Examples of organ systems in a human include the skeletal, nervous, and reproductive systems. |
Most hormones are controlled by what type of feedback, which causes the hormone to decrease its own production? | unusual | positive | neutral | negative | Most hormones are controlled by negative feedback in which the hormone feeds back to decrease its own production. This type of feedback brings things back to normal whenever they start to become too extreme. Positive feedback is much less common because it causes conditions to become increasingly extreme. |
What is the stage called for babies that are in the first year of life after birth? | adolescence | original stage | primary stage | infancy | Infancy is the first year of life after birth. Infants are born with a surprising range of abilities. For example, they have well-developed senses of touch, hearing, and smell. They can also communicate their needs by crying. During their first year, they develop many other abilities, including those described below. For a video of major milestones in the first year of life, go to this link: http://www. youtube. com/watch?v=5_Ao_3hTS6I . |
What forms a barrier between the cytoplasm and the environment outside the cell? | cell wall | cuticle | epidermis | plasma membrane | The plasma membrane forms a barrier between the cytoplasm and the environment outside the cell. The plasma membrane has selective permeability. |
Over time, what changes solid rock into pieces? | leaching | metamorphosis | creep | weathering | Weathering changes solid rock into pieces. These pieces are called sediments. Sediments are described in the chapter Earth's Materials and Crust . Sediments are different sizes of rock particles. Boulders are sediments; so is gravel. At the other end, silt and clay are also sediments. Weathering may also cause the minerals at the Earth’s surface to change form. The new minerals that form are stable at the Earth’s surface. There are two types of weathering, mechanical and chemical. These are discussed in the next two concepts. |
Eukaryotic cells undergo what kinds of divisions that more primitive cells do not? | homologous | budding | meiosis | mitosis | Mitosis , or division of the nucleus, occurs only in eukaryotic cells. By the time mitosis occurs, the cell’s DNA has already replicated. Mitosis occurs in four phases, called prophase, metaphase, anaphase, and telophase. You can see what happens in each phase in Figure below . The phases are described below. You can also learn more about the phases of mitosis by watching this video: https://www. youtube. com/watch?v=gwcwSZIfKlM . |
The orbicularis oris is a circular muscle that moves the lips, and the orbicularis oculi is a circular muscle that does what? | moisturizes the eye | pressure the eye | opens the eye | closes the eye | The orbicularis oris is a circular muscle that moves the lips, and the orbicularis oculi is a circular muscle that closes the eye. The occipitofrontalis muscle moves up the scalp and eyebrows. The muscle has a frontal belly and an occipital (near the occipital bone on the posterior part of the skull) belly. In other words, there is a muscle on the forehead ( frontalis) and one on the back of the head ( occipitalis), but there is no muscle across the top of the head. Instead, the two bellies are connected by a broad tendon called the epicranial aponeurosis, or galea aponeurosis (galea = “apple”). The physicians originally studying human anatomy thought the skull looked like an apple. The majority of the face is composed of the buccinator muscle, which compresses the cheek. This muscle allows you to whistle, blow, and suck; and it contributes to the action of chewing. There are several small facial muscles, one of which is the corrugator supercilii, which is the prime mover of the eyebrows. Place your finger on your eyebrows at the point of the bridge of the nose. Raise your eyebrows as if you were surprised and lower your eyebrows as if you were frowning. With these movements, you can feel the action of the corrugator supercilli. Additional muscles of facial expression are presented in Figure 11.8. |
What may have developed to help our ancestors distinguish between ripe and unripe fruits? | night vision | fine motor skills | acute hearing | color vision | McKay Savage. Color vision may have developed to help our ancestors distinguish between ripe and unripe fruits . CC BY 2.0. |
Which stage is specialized for dispersal & reproduction? | cocoon stage | fetal stage | larval stage | adult stage | |
What three parameters do seismographs measure? | trouble , length and distance | height, width and distance | aging , length and distance | strength, length and distance | Seismograms contain a lot of information about an earthquake: its strength, length and distance. Wave height used to determine the magnitude of the earthquake. The seismogram shows the different arrival times of the seismic waves ( Figure below ). The first waves are P-waves since they are the fastest. S-waves come in next and are usually larger than P-waves. The surface waves arrive just after the S-waves. If the earthquake has a shallow focus, the surface waves are the largest ones recorded. |
What topographic feature does a circle with inward hatches represent on a contour map? | a mountain | a lake | vegetation | a depression | On a contour map, a circle with inward hatches indicates a depression. |
Which temperatures cause particles of reactants to have more energy? | lower | non-existant | reducing | higher | When the temperature of reactants is higher, the rate of the reaction is faster. At higher temperatures, particles of reactants have more energy, so they move faster. They are more likely to bump into one another and to collide with greater force. For example, when you fry an egg, turning up the heat causes the egg to cook faster. The same principle explains why storing food in a cold refrigerator reduces the rate at which food spoils (see Figure below ). Both food frying and food spoiling are chemical reactions that happen faster at higher temperatures. |
Not all cells of a leaf carry out photosynthesis. cells within the middle layer of a leaf have chloroplasts, which contain the photosynthetic what? | wires | pipes | structure | apparatus | Figure 5.7 Not all cells of a leaf carry out photosynthesis. Cells within the middle layer of a leaf have chloroplasts, which contain the photosynthetic apparatus. (credit "leaf": modification of work by Cory Zanker). |
What is the advantage of selecting for certain genetic traits for crops? | Faster growth | protection from pests | improves taste | promotes productivity | Improving crops by selecting for certain genetic traits. The desired traits promote productivity. Recently, genetically engineered crops have been introduced. |
What is given off from plants and taken in by animals? | nitrogen | methane | sulfur | oxygen | |
What is the simplest unit that has the fundamental chemical properties of an element? | cell | neutron | nucleus | atom | Covalent Molecules and Compounds Just as an atom is the simplest unit that has the fundamental chemical properties of an element, a molecule is the simplest unit that has the fundamental chemical properties of a covalent compound. Some pure elements exist as covalent molecules. Hydrogen, nitrogen, oxygen, and the halogens occur naturally. |
Bacteria are what kind of cell? | eukaryotes | protists | blood | prokaryotes | The rod-shaped organisms in Figure below are bacteria called Salmonella . Bacteria (bacterium, singular) are prokaryotes in the Bacteria Domain. The word Salmonella may sound familiar. That's because Salmonella is a common cause of food poisoning. Many other types of bacteria also cause human diseases. But not all bacteria are harmful to people. In fact, we could not survive without many of the trillions of bacteria that live in or on the human body. You'll learn why when you read this lesson. |
What is the first stage of cellular respiration? | decarboxylation | gluconeogenesis | Krebs cycle | glycolysis | The first stage of cellular respiration is glycolysis. It does not require oxygen. |
Who study volcanoes to be able to predict when a volcano will erupt? | ornithologists | vocologists | virologists | volcanologists | Volcanic eruptions can be devastating, particularly to the people who live close to volcanoes. Volcanologists study volcanoes to be able to predict when a volcano will erupt. Many changes happen when a volcano is about to erupt. |
What is the term for electric current that keeps reversing direction? | magnetic current | direct current | AC/DC | alternating current | The Figure below shows the direction of the current that is generated by a moving magnet. If the magnet is moved back and forth repeatedly, the current keeps changing direction. In other words, alternating current (AC) is produced. Alternating current is electric current that keeps reversing direction. |
How many alleles comes from each parent? | three | none | two | one | When gametes unite during fertilization, the resulting zygote inherits two alleles for each gene. One allele comes from each parent. |
How close a measurement is to the correct value for that measurement is known as what? | temperature | frequency | rate | accuracy | Accuracy and Precision of a Measurement Science is based on observation and experiment—that is, on measurements. Accuracy is how close a measurement is to the correct value for that measurement. For example, let us say that you are measuring the length of standard computer paper. The packaging in which you purchased the paper states that it is 11.0 inches long. You measure the length of the paper three times and obtain the following measurements: 11.1 in. , 11.2 in. , and 10.9 in. These measurements are quite accurate because they are very close to the correct value of 11.0 inches. In contrast, if you had obtained a measurement of 12 inches, your measurement would not be very accurate. The precision of a measurement system is refers to how close the agreement is between repeated measurements (which are repeated under the same conditions). Consider the example of the paper measurements. The precision of the measurements refers to the spread of the measured values. One way to analyze the precision of the measurements would be to determine the. |
What pigment is required for photosynthesis to occur? | xanthophyll | carotene | chroma | chlorophyll | |
What begins approximately six weeks after fertilization in an embryo? | incubation | calcification | elongation | ossification | Development of Bone Ossification, or osteogenesis, is the process of bone formation by osteoblasts. Ossification is distinct from the process of calcification; whereas calcification takes place during the ossification of bones, it can also occur in other tissues. Ossification begins approximately six weeks after fertilization in an embryo. Before this time, the embryonic skeleton consists entirely of fibrous membranes and hyaline cartilage. The development of bone from fibrous membranes is called intramembranous ossification; development from hyaline cartilage is called endochondral ossification. Bone growth continues until approximately age 25. Bones can grow in thickness throughout life, but after age 25, ossification functions primarily in bone remodeling and repair. |
What do you call the energy that must be overcome in order for a chemical reaction to occur, or the minimum energy required to start a chemical reaction? | kinetic energy | expression energy | phase energy | activation energy | Regardless of whether reactions are exothermic reactions or endothermic reactions , they all need energy to get started. This energy is called activation energy . Activation energy is like the push you need to start moving down a slide. The push gives you enough energy to start moving. Once you start, you keep moving without being pushed again. Activation energy is defined as the energy that must be overcome in order for a chemical reaction to occur, or the minimum energy required to start a chemical reaction. The concept of activation energy is illustrated in Figure below . |
Frogs and toads, salamanders and newts, and caecilians are the three orders of what group of animals? | mammals | marsupials | reptiles | amphibians | There are about 6,200 known species of living amphibians. They are classified into three orders: frogs and toads, salamanders and newts, and caecilians. |
What are vesicles made of? | filaments | cells | membranes | phospholipids | A vesicle. Because vesicles are made of phospholipids, they can break off of and fuse with other membraneous material. This allows them to serve as small transport containers, moving substances around the cell and to the cell membrane. |
Deoxyribonucleic acid (dna) is nucleotide that stores what type of information? | variation | mononucleus | mutation | genetic | Nucleic Acids The nucleic acids differ in their type of pentose sugar. Deoxyribonucleic acid (DNA) is nucleotide that stores genetic information. DNA contains deoxyribose (so-called because it has one less atom of oxygen than ribose) plus one phosphate group and one nitrogen-containing base. The “choices” of base for DNA are adenine, cytosine, guanine, and thymine. Ribonucleic acid (RNA) is a ribose-containing nucleotide that helps manifest the genetic code as protein. RNA contains ribose, one phosphate group, and one nitrogen-containing base, but the “choices” of base for RNA are adenine, cytosine, guanine, and uracil. The nitrogen-containing bases adenine and guanine are classified as purines. A purine is a nitrogen-containing molecule with a double ring structure, which accommodates several nitrogen atoms. The bases cytosine, thymine (found in DNA only) and uracil (found in RNA only) are pyramidines. A pyramidine is a nitrogen-containing base with a single ring structure Bonds formed by dehydration synthesis between the pentose sugar of one nucleic acid monomer and the phosphate group of another form a “backbone,” from which the components’ nitrogen-containing bases protrude. In DNA, two such backbones attach at their protruding bases via hydrogen bonds. These twist to form a shape known as a double helix (Figure 2.29). The sequence of nitrogen-containing bases within a strand of DNA form the genes that act as a molecular code instructing cells in the assembly of amino acids into proteins. Humans have almost 22,000 genes in their DNA, locked up in the 46 chromosomes inside the nucleus of each cell (except red blood cells which lose their nuclei during development). These genes carry the genetic code to build one’s body, and are unique for each individual except identical twins. |
What two basic types of feather does a bird have? | flight and landing | carrying and down | up and down | flight and down | Feathers help birds fly and also provide insulation and serve other purposes. Birds actually have two basic types of feathers: flight feathers and down feathers. Both are shown in Figure below . Flight feathers are long, stiff and waterproof. They provide lift and air resistance without adding weight. Down feathers are short and fluffy. They trap air next to a bird’s skin for insulation. |
Which fuels provide most of the world’s energy? | artificial fuels | coal fuels | pattern fuels | fossil fuels | Figure below shows the mix of energy resources used worldwide in 2006. Fossil fuels still provide most of the world’s energy, with oil being the single most commonly used energy resource. Natural gas is used less than the other two fossil fuels, but even natural gas is used more than all renewable energy resources combined. Wind, solar, and geothermal energy contribute the least to global energy use, despite the fact that they are virtually limitless in supply and nonpolluting. |
The cathode and anode collectively are the electrodes of what? | photo cell | circuit cell | switch cell | voltaic cell | One application of redox reactions requires that they be physically separated. Even though the two half reactions are physically separated, a spontaneous redox reaction still occurs. However, in this case, the electrons transfer through the wire connecting the two half reactions; that is, this setup becomes a source of electricity. Useful work can be extracted from the electrons as they transfer from one side to the other—for example, a light bulb can be lit, or a motor can be operated. The apparatus as a whole, which allows useful electrical work to be extracted from a redox reaction, is called a voltaic (galvanic) cell. Each individual system that contains a half reaction is called a half cell. The half cell that contains the oxidation reaction is called the anode, while the half cell that contains the reduction reaction is called the cathode. The cathode and anode collectively are the electrodes of the voltaic cell. Because electrons are coming from the anode, the anode is considered the negative electrode of the cell, while the cathode is considered the positive electrode of the cell. Finally, because electrons are moving from one half cell to the. |
What part of the sweet potato store sugar from photosynthesis as starch? | shrubs | plants | skin | roots | Secondary growth of sweet potato roots provides more space to store food. Roots store sugar from photosynthesis as starch. What other starchy roots do people eat?. |
What is the ratio of charge on a capacitor to potential difference across it called? | resonance | velocity | electromagnetism | capacitance | When a capacitor is placed in a circuit, current does not actually travel across it. Rather, equal and opposite charge begins to build up on opposite sides of the capacitor --- mimicking a current --- until the electric field in the capacitor creates a potential difference across it that balances the voltage drop across any parallel resistors or the voltage source itself (if there are no resistors in parallel with the capacitor). The ratio of charge on a capacitor to potential difference across it is called capacitance. |
What substances that primarily comprise plasma membranes form a bilayer? | steroids | amino acids | enzymes | phospholipids | Plasma membranes are primarily made up of phospholipids (orange). The hydrophilic ("water-loving") head and two hydrophobic ("water-hating") tails are shown. The phospholipids form a bilayer (two layers). The middle of the bilayer is an area without water. There can be water on either side of the bilayer. There are many proteins throughout the membrane. |
What type of friction is friction that acts on objects when they are sliding over a surface? | rolling friction | spreading friction | static friction | sliding friction | Sliding friction is friction that acts on objects when they are sliding over a surface. Sliding friction is weaker than static friction. That’s why it’s easier to slide a piece of furniture over the floor after you start it moving than it is to get it moving in the first place. Sliding friction can be useful. For example, you use sliding friction when you write with a pencil. The pencil “lead” slides easily over the paper, but there’s just enough friction between the pencil and paper to leave a mark. |
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