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Energy is lost as heat between each trophic level due to the second law of what? | chemistry | reactions | particles | thermodynamics | One major factor that limits the length of food chains is energy. Energy is lost as heat between each trophic level due to the second law of thermodynamics. Thus, after a limited number of trophic energy transfers, the amount of energy remaining in the food chain may not be great enough to support viable populations at yet a higher trophic level. The loss of energy between trophic levels is illustrated by the pioneering studies of Howard T. Odum in the Silver Springs, Florida, ecosystem in the 1940s (Figure 46.5). The primary producers generated 20,819 kcal/m2/yr (kilocalories per square meter per year), the primary consumers generated 3368 kcal/m2/yr, the secondary consumers generated 383 kcal/m2/yr, and the tertiary consumers only generated 21 kcal/m2/yr. Thus, there is little energy remaining for another level of consumers in this ecosystem. |
What are electrons in the outer energy level of an atom called? | positive electrons | shell electrons | outer electrons | valence electrons | The electrons in the outer energy level of an atom are called valence electrons . It is valence electrons that are potentially involved in chemical reactions. The number of valence electrons determines an element’s reactivity, or how likely the element is to react with other elements. The number of valence electrons also determines whether the element can conduct electric current. That’s because electric current is the flow of electrons. Table below shows how these properties vary in elements from each class. |
Halogens tend to form salts with what type of element? | man-made | nonmetals | metalloids | metals | Halogens have filled valence electron configurations. Halogens tend to form salts with metals. As the free elements, halogens are monatomic. Halogens have appreciable nonmetallic character. Halogens tend to have an oxidation state of −1. Halogens are good reductants. |
The voltage is measured using a voltmeter, which measures which difference across two points? | average difference | Distance | actual difference | potential difference | A uniform electric field makes it easier to measure the difference in electric potential energy. This energy, also called the electric potential difference is commonly referred to as the voltage , based on the unit, volt (V). To measure the voltage across some distance, it is necessary to pick a position to be the relative zero, because voltage is the change in potential difference. Any point in a system can be given the value of zero volts, but it is typically the point of a point charge or one plate in a uniform electric field as shown above. The voltage is measured using a voltmeter, which measures the electric potential difference across two points. |
What is the vertical extent of ocean water called? | water row | oceanic pillar | ocean column | water column | Scientists refer to the vertical extent of ocean water as the water column . Two main zones based on depth of water are the photic zone and aphotic zone. The photic zone is the top 200 meters of water. The aphotic zone is water deeper than 200 meters. The deeper you go, the darker the water gets. That’s because sunlight cannot penetrate very far under water. Sunlight is needed for photosynthesis. So the depth of water determines whether photosynthesis is possible. There is enough sunlight for photosynthesis only in the photic zone. |
Echinoderms are found in many different ocean environments, but most are found where? | in waterfalls | in tidepools | in beaches | in reefs | Echinoderms are found in many different ocean environments, but most are found in reefs. |
A convergent plate boundary is created when two plates do what? | stay stationary | move away from each other | move perpendicular to each other | come toward each other | When two plates come toward each other, they create a convergent plate boundary. |
When volcanoes erupt, what from the mantle is released as carbon dioxide into the air? | vapor | lava | hydrogen | carbon | Carbon from decaying organisms enters the ground. Some carbon is stored in the soil. Some carbon may be stored underground for millions of years. This will form fossil fuels. When volcanoes erupt, carbon from the mantle is released as carbon dioxide into the air. Producers take in the carbon dioxide to make food. Then the cycle repeats. |
Sepals, petals, pistils, and stamens are contained in all what, which are actually modified leaves or sporophylls organized around a central stalk? | stems | chlorophyll | roots | flowers | Flowers Flowers are modified leaves or sporophylls organized around a central stalk. Although they vary greatly in appearance, all flowers contain the same structures: sepals, petals, pistils, and stamens. A whorl of sepals (the calyx) is located at the base of the peduncle, or stem, and encloses the floral bud before it opens. Sepals are usually photosynthetic organs, although there are some exceptions. For example, the corolla in lilies and tulips consists of three sepals and three petals that look virtually identical—this led botanists to coin the word tepal. Petals (collectively the corolla) are located inside the whorl of sepals and usually display vivid colors to attract pollinators. Flowers pollinated by wind are usually small and dull. The sexual organs are located at the center of the flower. As illustrated in Figure 14.25, the stigma, style, and ovary constitute the female organ, the carpel or pistil, which is also referred to as the gynoecium. A gynoecium may contain one or more carpels within a single flower. The megaspores and the female gametophytes are produced and protected by the thick tissues of the carpel. A long, thin structure called a style leads from the sticky stigma, where pollen is deposited, to the ovary enclosed in the carpel. The ovary houses one or more ovules that will each develop into a seed upon fertilization. The male reproductive organs, the androecium or stamens, surround the central carpel. Stamens are composed of a thin stalk called a filament and a sac-like structure, the anther, in which microspores are produced by meiosis and develop into pollen grains. The filament supports the anther. |
What do cells do in order to replace damaged or worn out cells? | fold | replicate | die | divide | Cells also divide in order to replace damaged or worn-out cells. |
What kind of agriculture destroyed about 10% of madagascar's native plants? | fertilizer use | hybridization | crop rotation | slash-and-burn | Another example of species loss due to habitat destruction happened on Madagascar’s central highland plateau. From 1970 to 2000, slash-and-burn agriculture destroyed about 10% of the country’s total native plants. The area turned into a wasteland. Soil from erosion entered the waterways. Much of the river ecosystems of several large rivers were also destroyed. Several fish species are almost extinct. Also, some coral reef formations in the Indian Ocean are completely lost. |
Chloroplasts are the little green particles in plants made up of what colorful pigment? | melanin | verdigris | carbonate | chlorophyll | |
What is the largest organ of the human body? | your blood | your lungs | your brain | your skin | You couldn’t survive without your skin. It has many important functions. In several ways, it helps maintain homeostasis. The main function of the skin is controlling what enters and leaves the body. It prevents the loss of too much water from the body. It also prevents bacteria and other microorganisms from entering the body. Melanin in the epidermis absorbs ultraviolet light. This prevents the light from reaching and damaging the dermis. |
What kind of charge does a proton have? | negative | ionic | constant | positive | Electric charge is a physical property of particles or objects that causes them to attract or repel each other without touching. All electric charge is based on the protons and electrons in atoms. A proton has a positive electric charge, and an electron has a negative electric charge (see Figure below ). |
What are boggy regions with thick layers of peat called? | meadows | wetlands | tropics | peatlands | |
What type of compounds make up the cells and tissues of living things? | proximal | hormonal | microbial | biochemical | Biochemical compounds make up the cells and tissues of living things. They are also involved in all life processes. Given their diversity of functions, it’s not surprising that there are millions of different biochemical compounds. Even so, all biochemical compounds can be grouped into just four main classes: carbohydrates, proteins, lipids, and nucleic acids. The classes are summarized in Table below . |
Anything that has mass and takes up space is considered what? | power | energy | light | matter | Matter is anything that has mass and takes up space. Matter is everywhere. The air we breathe, the water we drink, the food we eat, and the ground we walk on are all comprised of matter. Matter can take on a variety of different forms which all have a variety of different properties. In this chapter, we will introduce the characteristics of matter and study how these characteristics vary in different types of matter. |
What will you see if you look at a star through a prism? | spots | kaleidoscope | rainbow | spectrum | If you look at a star through a prism, you will see a spectrum . The spectrum is the range of colors seen in a rainbow. The spectrum has specific dark bands where elements in the star have absorbed light of certain energies. An astronomer can use these lines to determine which elements are in a distant star. In fact, the element helium was first discovered in our Sun, not on Earth. This was done by analyzing the absorption lines in the spectrum of the sun. |
Where is most digestion completed? | the esophagus | the cavity | the stomach | the duodenum | |
Explosive eruptions associated with what can be tens of thousands of times as powerful as an atomic bomb? | earthquakes | forest fires | hurricanes | volcanoes | An explosive eruption produces huge clouds of volcanic ash. Chunks of the volcano fly high into the atmosphere. Explosive eruptions can be tens of thousands of times as powerful as an atomic bomb ( Figure below ). Hot magma beneath the surface mixes with water. This forms gases. The gas pressure grows until it must be released. The volcano erupts in an enormous explosion. |
What gland secretes its products directly into the urethra through several small ducts | thyroid | pituitary | adrenal | prostate | |
The complete combustion of alkanes to carbon dioxide is an extremely __________ reaction. | reactive | hydrolic | geothermal | exothermic | Each step in the process is either a gain of oxygen or a loss of hydrogen. Each step also releases energy, which explains why the complete combustion of alkanes to carbon dioxide is an extremely exothermic reaction. |
What is the study of structure, properties, and interactions of matter? | geology | petrology | biology | chemistry | Chemistry is the study of the structure, properties, and interactions of matter. Important concepts in chemistry include physical changes, such as water freezing, and chemical reactions, such as fireworks exploding. Chemistry concepts can answer all the questions on the left page of the notebook in Figure below . Do you know the answers?. |
Because several genes, each with more than one allele, contribute to determining height in humans, height is considered what kind of trait? | epigenetic | adaptive | maladaptive | polygenic | An example of a human polygenic trait is adult height. Several genes, each with more than one allele, contribute to this trait, so there are many possible adult heights. For example, one adult’s height might be 1.655 m (5.430 feet), and another adult’s height might be 1.656 m (5.433 feet) tall. Adult height ranges from less than 5 feet to more than 6 feet, but the majority of people fall near the middle of the range, as shown in Figure below . |
A basidium is the fruiting body of a mushroomproducing fungus, and it forms four what? | fossiliferous | schizonts | tunnels | basidiocarps | Figure 24.16 Which of the following statements is true? a. A basidium is the fruiting body of a mushroomproducing fungus, and it forms four basidiocarps. The result of the plasmogamy step is four basidiospores. Karyogamy results directly in the formation of mycelia. A basidiocarp is the fruiting body of a mushroom-producing fungus. Figure 24.20 If symbiotic fungi are absent from the soil, what impact do you think this would have on plant growth?. |
Traditional classification of mammals are based on similarities in what two things? | Density and Structure | solution & function | density & function | structure & function | |
The rest of the energy stored in glucose is lost as what? | humidity | mass | volume | heat | |
Water that is lost through the skin through evaporation from the skin surface without overt sweating and from air expelled from the lungs is known as what? | logical water loss | dehydration | osmotic process | insensible water loss | 26.2 | Water Balance By the end of this section, you will be able to: • Explain how water levels in the body influence the thirst cycle • Identify the main route by which water leaves the body • Describe the role of ADH and its effect on body water levels • Define dehydration and identify common causes of dehydration On a typical day, the average adult will take in about 2500 mL (almost 3 quarts) of aqueous fluids. Although most of the intake comes through the digestive tract, about 230 mL (8 ounces) per day is generated metabolically, in the last steps of aerobic respiration. Additionally, each day about the same volume (2500 mL) of water leaves the body by different routes; most of this lost water is removed as urine. The kidneys also can adjust blood volume though mechanisms that draw water out of the filtrate and urine. The kidneys can regulate water levels in the body; they conserve water if you are dehydrated, and they can make urine more dilute to expel excess water if necessary. Water is lost through the skin through evaporation from the skin surface without overt sweating and from air expelled from the lungs. This type of water loss is called insensible water loss because a person is usually unaware of it. |
What are the only innate behaviors in humans? | insight behaviors | learned behaviors | inherited traits | reflex behaviors | Innate behaviors occur in all animals. However, the more intelligent a species is, the fewer innate behaviors it generally has. The human species is the most intelligent animal species, and it has very few innate behaviors. The only innate behaviors in humans are reflex behaviors. A reflex behavior is a simple response that always occurs when a certain stimulus is present. |
What occurs when a parent organism breaks into fragments, or pieces, and each fragment develops into a new organism? | sollution | erosion | absorption | fragmentation | Fragmentation occurs when a parent organism breaks into fragments, or pieces, and each fragment develops into a new organism. Starfish, like the one in Figure below , reproduce this way. A new starfish can develop from a single ray, or arm. Starfish, however, are also capable of sexual reproduction. |
What does the triploid cell develop into during fertilization? | zygote | membrane | tubers | endosperm | Double Fertilization After pollen is deposited on the stigma, it must germinate and grow through the style to reach the ovule. The microspores, or the pollen, contain two cells: the pollen tube cell and the generative cell. The pollen tube cell grows into a pollen tube through which the generative cell travels. The germination of the pollen tube requires water, oxygen, and certain chemical signals. As it travels through the style to reach the embryo sac, the pollen tube’s growth is supported by the tissues of the style. In the meantime, if the generative cell has not already split into two cells, it now divides to form two sperm cells. The pollen tube is guided by the chemicals secreted by the synergids present in the embryo sac, and it enters the ovule sac through the micropyle. Of the two sperm cells, one sperm fertilizes the egg cell, forming a diploid zygote; the other sperm fuses with the two polar nuclei, forming a triploid cell that develops into the endosperm. Together, these two fertilization. |
The law of conservation of matter, which says that matter cannot be created or this? | stopped | abandoned | damaged | destroyed | the law of conservation of matter, which says that matter cannot be created or destroyed. This means we must have the same number of protons and neutrons on both sides of the nuclear equation. If our uranium nucleus loses 2 protons, there are 90 protons remaining, identifying the element as thorium. Moreover, if we lose four nuclear particles of the original 235, there are 231 remaining. Thus we use subtraction to identify the isotope of the Th atom—in this case,. |
Which particle of an atom has a positive electric charge? | nucleus | electron | nutron | proton | A proton is a particle in the nucleus of an atom that has a positive electric charge. All protons are identical. It is the number of protons that gives atoms of different elements their unique properties. Atoms of each type of element have a characteristic number of protons. For example, each atom of carbon has six protons, as you can see in Figure below . No two elements have atoms with the same number of protons. |
How is a reaction described when the given conditions favor formation of products? | planned | instantaneous | fluctuations | spontaneous | Chemists want to be able to predict the outcome of reactions. They would like it to be possible to predict what will happen when reactants are added together under a given set of conditions. The conditions of a reaction might include things like temperature, pressure, and concentrations of various reaction components. If the given conditions favor the formation of products, the reaction is said to be spontaneous . |
What does an electric field surround? | charged ions | neutral particles | negative particle | a charged particle | An electric field is a space surrounding a charged particle where the particle exerts electric force. |
Lack of what mineral causes rickets? | magnesium | zinc | potassium | calcium | Rickets is softening of the bones in children that occurs because bones do not have enough calcium. Rickets can lead to fractures and bowing of the leg bones, which is illustrated in the Figure below . |
What do we call the energy of motion? | binary energy | electromagnetic energy | harmonic energy | kinetic energy | The energy of motion is called kinetic energy. |
Earthquakes and visible light are examples of what? | winds | geological phenomena | currents | waves | Introduction to Oscillatory Motion and Waves What do an ocean buoy, a child in a swing, the cone inside a speaker, a guitar, atoms in a crystal, the motion of chest cavities, and the beating of hearts all have in common? They all oscillate—-that is, they move back and forth between two points. Many systems oscillate, and they have certain characteristics in common. All oscillations involve force and energy. You push a child in a swing to get the motion started. The energy of atoms vibrating in a crystal can be increased with heat. You put energy into a guitar string when you pluck it. Some oscillations create waves. A guitar creates sound waves. You can make water waves in a swimming pool by slapping the water with your hand. You can no doubt think of other types of waves. Some, such as water waves, are visible. Some, such as sound waves, are not. But every wave is a disturbance that moves from its source and carries energy. Other examples of waves include earthquakes and visible light. Even subatomic particles, such as electrons, can behave like waves. By studying oscillatory motion and waves, we shall find that a small number of underlying principles describe all of them and that wave phenomena are more common than you have ever imagined. We begin by studying the type of force that underlies the simplest oscillations and waves. We will then expand our exploration of oscillatory motion and waves to include concepts such as simple harmonic motion, uniform circular motion, and damped harmonic motion. Finally, we will explore what happens when two or more waves share the same space, in the phenomena known as superposition and interference. |
There is always a slightly negative pressure within what cavity, helping keep the airways of the lungs open? | spinal | anal | cervical | thoracic | There is always a slightly negative pressure within the thoracic cavity, which aids in keeping the airways of the lungs open. During inhalation, volume increases as a result of contraction of the diaphragm, and pressure decreases (according to Boyle’s Law). This decrease of pressure in the thoracic cavity relative to the environment makes the cavity less than the atmosphere (Figure 39.16a). Because of this drop in pressure, air rushes into the respiratory passages. To increase the volume of the lungs, the chest wall expands. This results from the contraction of the intercostal muscles, the muscles that are connected to the rib cage. Lung volume expands because the diaphragm contracts and the intercostals muscles contract, thus expanding the thoracic cavity. This increase in the volume of the thoracic cavity lowers pressure compared to the atmosphere, so air rushes into the lungs, thus increasing its volume. The resulting increase in volume is largely attributed to an increase in alveolar space, because the bronchioles and bronchi are stiff structures that do not change in size. |
What property allows cut logs to float on water? | precipitation | polarity | heat | density | After trees are cut, logging companies often move these materials down a river to a sawmill where they can be shaped into building materials or other products. The logs float on the water because they are less dense than the water they are in. Knowledge of density is important in the characterization and separation of materials. Information about density allows us to make predictions about the behavior of matter. |
Different interatomic distances produce different lattice what? | weights | qualities | surfaces | energies | in which C is a constant that depends on the type of crystal structure; Z+ and Z– are the charges on the ions; and Ro is the interionic distance (the sum of the radii of the positive and negative ions). Thus, the lattice energy of an ionic crystal increases rapidly as the charges of the ions increase and the sizes of the ions decrease. When all other parameters are kept constant, doubling the charge of both the cation and anion quadruples the lattice energy. For example, the lattice energy of LiF (Z+ and Z– = 1) is 1023 kJ/mol, whereas that of MgO (Z+ and Z– = 2) is 3900 kJ/ mol (Ro is nearly the same—about 200 pm for both compounds). Different interatomic distances produce different lattice energies. For example, we can compare the lattice energy of MgF2 (2957 kJ/mol) to that of MgI2 (2327 kJ/mol) to observe the effect on lattice energy of the smaller ionic size of F– as compared to I–. |
What organs filter blood and form urine? | the liver | the appendix | the spleen | the kidneys | The kidneys filter blood and form urine. They are part of the urinary system, which also includes the ureters, bladder, and urethra. |
A chain of what structures form as an oceanic plate moves over a hotspot? | outcrops | ridges | earthquakes | volcanoes | A chain of volcanoes form as an oceanic plate moves over a hotspot. This is how it happens. A volcano forms over the hotspot. Since the plate is moving, the volcano moves off of the hotspot. When the hotspot erupts again, a new volcano forms over it. This volcano is next to the first. Over time, there is a line of volcanoes. The youngest is directly above the hotspot. The oldest is the farthest away ( Figure below ). |
What is responsible for many properties of covalent compounds, which have relatively low boiling points, cannot conduct electricity, and may not dissolve in water? | atomic weight | ionic charge | accretion bonds | covalent bonds | Covalent bonds are responsible for many of the properties of covalent compounds. Covalent compounds have relatively low boiling points, cannot conduct electricity, and may not dissolve in water. |
Tanning salons claim to use a “safe” form of what light, with a longer wavelength than that in sunlight? | X rays | infrared | microwave | uv (ultraviolet) | 29.3 Photon Energies and the Electromagnetic Spectrum 11. Why are UV, x rays, and γ rays called ionizing radiation? 12. How can treating food with ionizing radiation help keep it from spoiling? UV is not very penetrating. What else could be used? 13. Some television tubes are CRTs. They use an approximately 30-kV accelerating potential to send electrons to the screen, where the electrons stimulate phosphors to emit the light that forms the pictures we watch. Would you expect x rays also to be created? 14. Tanning salons use “safe” UV with a longer wavelength than some of the UV in sunlight. This “safe” UV has enough photon energy to trigger the tanning mechanism. Is it likely to be able to cause cell damage and induce cancer with prolonged exposure? 15. Your pupils dilate when visible light intensity is reduced. Does wearing sunglasses that lack UV blockers increase or decrease the UV hazard to your eyes? Explain. One could feel heat transfer in the form of infrared radiation from a large nuclear bomb detonated in the atmosphere 75 km from you. However, none of the profusely emitted x rays or γ rays reaches you. Explain. Can a single microwave photon cause cell damage? Explain. In an x-ray tube, the maximum photon energy is given by. |
Respiratory therapists or respiratory practitioners evaluate and treat patients diseases affecting what part of the body? | heart, lungs, stomach | byproduct , heart , and blood vessels | brain, stomach, heart | lung, heart, and blood vessels | Respiratory Therapist Respiratory therapists or respiratory practitioners evaluate and treat patients with lung and cardiovascular diseases. They work as part of a medical team to develop treatment plans for patients. Respiratory therapists may treat premature babies with underdeveloped lungs, patients with chronic conditions such as asthma, or older patients suffering from lung disease such as emphysema and chronic obstructive pulmonary disease (COPD). They may operate advanced equipment such as compressed gas delivery systems, ventilators, blood gas analyzers, and resuscitators. Specialized programs to become a respiratory therapist generally lead to a bachelor’s degree with a respiratory therapist specialty. Because of a growing aging population, career opportunities as a respiratory therapist are expected to remain strong. |
Within each sporangium, hundreds of what kind of spores develop and are dispersed through the air? | infertile | diploid | polyploid | haploid | |
What delivers power to the chemical factory chloroplasts? | chlorophyll | oxygen | water | the sun | |
Which type of bryophytes are named for their horn-like sporophytes? | tapeworms | arthropods | flatworms | hornworts | Liverworts, hornworts, and mosses are modern bryophytes. Liverworts are named for the liver-shaped leaves of some species. Hornworts are named for their horn-like sporophytes. |
What do you call a carnivore that eats mainly insects? | omnivores | pescatorian | predator | insectivores | Mammals may be herbivores, carnivores, or omnivores. Some carnivore mammals eat mainly insects and are called insectivores. Some omnivore mammals eat mainly fruits and are called frugivores. |
Oxygen has the second highest electronegativity of any element; consequently, it prefers to share or accept electrons from other elements. only with fluorine does oxygen form compounds in this? | negative Oxidation States | liquid oxidation states | chemical oxidation states | positive oxidation states | Oxygen has the second highest electronegativity of any element; consequently, it prefers to share or accept electrons from other elements. Only with fluorine does oxygen form compounds in positive oxidation states. |
What component of cells is present in plant and bacterial cells but not animal cells? | mitochondria | nucleus | plasma | cell wall | Animal Cell. The shape of an animal cell is not constrained by a rigid cell wall. A bacterial cell is shown above for comparison. |
Energy cannot be created or destroyed - it can only change what? | shape | kind | fluid | form | All living things need energy. They need it to power the processes of life. For example, it takes energy to grow. It also takes energy to produce offspring. In fact, it takes energy just to stay alive. Remember that energy can’t be created or destroyed. It can only change form. Energy changes form as it moves through ecosystems. |
Most fungi can reproduce in which 2 ways? | sexually and binary fusion | binary fission and fusion | sexually and autonomously | asexually and sexually | The majority of fungi can reproduce both asexually and sexually. This allows them to adjust to conditions in the environment. They can spread quickly through asexual reproduction when conditions are stable. They can increase their genetic variation through sexual reproduction when conditions are changing and variation may help them survive. |
What is a pair of valence electrons in a bonded atom that does not participate in bonding called? | hostile pair | opposite pair | isolated pair | lone pair | A pair of valence electrons in a bonded atom that does not participate in bonding is called a lone pair. Lone pair electrons contribute to molecular shape. |
When a metal is oxidized and a nonmetal is reduced in a redox reaction, what is the resulting compound called? | magnetic compound | soluble compound | alloy | ionic compound | There are many other examples of redox reactions in which two neutral elements combine to make a compound. These often take the form of a metal being oxidized and a nonmetal being reduced, resulting in an ionic compound. Two nonmetallic elements can also undergo a redox reaction of this type, in which the less electronegative element is oxidized and the more electronegative element is reduced. |
A biofilm is a colony of prokaryotes that is stuck to what? | skin | the middle | the bottom | surface | Some prokaryotes form structures consisting of many individual cells, like the cells in Figure below . This is called a biofilm. A biofilm is a colony of prokaryotes that is stuck to a surface. The surface might be a rock or a host's tissues. The sticky plaque that collects on your teeth between brushings is a biofilm. It consists of millions of prokaryotic cells. |
What is the part of the flower that produces pollen? | leaves | cones | stigma | stamen | stamens The part of the flower that produces pollen. |
What neutralizes the acidity of chyme and acts as a buffer? | the chloride | bile | the small intestine | the bicarbonate | |
What type of stress causes horizontal motions in strike-slip faults? | blunt | hot | cold | shear | |
The structure of the boeing 787 has been described as essentially one giant macromolecule, where everything is fastened through cross-linked chemical bonds reinforced with this? | metal-metal bonds | nitrogen fiber | non-covalent interaction | carbon fiber | carbon fiber–epoxy and boron fiber–epoxy composites. Compared with metals, these materials are 25%– 50% lighter and thus reduce operating costs. Similarly, the space shuttle payload bay doors and panels are made of a carbon fiber–epoxy composite. The structure of the Boeing 787 has been described as essentially one giant macromolecule, where everything is fastened through cross-linked chemical bonds reinforced with carbon fiber. Metal-matrix composites consist of metals or metal alloys reinforced with fibers. They offer significant advantages for high-temperature applications but pose major manufacturing challenges. For example, obtaining a uniform distribution and alignment of the reinforcing fibers can be difficult, and because organic polymers cannot survive the high temperatures of molten metals, only fibers composed of boron, carbon, or ceramic (such as silicon carbide) can be used. Aluminum alloys reinforced with boron fibers are used in the aerospace industry, where their strength and lightweight properties make up for their relatively high cost. The skins of hypersonic aircraft and structural units in the space shuttle are made of metal-matrix composites. Ceramic-matrix composites contain ceramic fibers in a ceramic matrix material. A typical example is alumina reinforced with silicon carbide fibers. Combining the two very high-melting-point materials results in a composite that has excellent thermal stability, great strength, and corrosion resistance, while the SiC fibers reduce brittleness and cracking. Consequently, these materials are used in very hightemperature applications, such as the leading edge of wings of hypersonic airplanes and jet engine parts. They are also used in the protective ceramic tiles on the space shuttle, which contain short fibers of pure SiO2 mixed with fibers of an aluminum–boron–silicate ceramic. These tiles are excellent thermal insulators and extremely light (their density is only about 0.2 g/cm3). Although their surface reaches a temperature of about 1250°C during reentry into Earth’s atmosphere, the temperature of the underlying aluminum alloy skin stays below 200°C. |
What is the term for the process in which two atomic nuclei fuse together to make a single nucleus? | binding | absorption | fission | fusion | Fusion is the process in which two atomic nuclei fuse together to make a single nucleus. Energy is released in the form of nuclear particles, neutrons, and gamma-rays. |
In human beings, when a female becomes pregnant, what is fertilized and then embedded in the uterus? | sperm | dna | follicle | egg | If the egg is fertilized, the egg makes its way through the fallopian tube into the uterus, where it imbeds into the thick lining. When this occurs, the monthly cycle stops. The monthly cycle does not resume until the pregnancy is over. |
What has increased the greenhouse effect? | climate change | ozone depletion | temperature changes | human actions | Greenhouse gases in the atmosphere absorb heat. This is called the greenhouse effect and it makes the planet warmer. Human actions have increased the greenhouse effect. |
How many pairs of chromosomes are there? | 24 | 16 | 25 | 23 | During anaphase I the spindle fibers shorten, and the homologous chromosome pairs are separated from each other. This occurs as the chiasmata are severed, pulling homologous chromosomes apart. One chromosome from each pair moves toward one pole, with the other moving toward the other pole, resulting in a cell with 23 chromosomes at one pole and the other 23 at the other pole. Each chromosome still contains a pair of sister chromatids; the sister chromatids remain attached at the centromere. |
What structure passes oxygen and nutrients to a growing fetus in mammals? | vas deferens | uterus | spinal cord | placenta | The majority of mammals are placental mammals. These are mammals in which the developing baby is fed through the mother's placenta. Female placental mammals develop a placenta after fertilization. A placenta is a spongy structure that passes oxygen, nutrients, and other useful substances from the mother to the fetus. It also passes carbon dioxide and other wastes from the fetus to the mother. The placenta allows the fetus to grow for a long time within the mother. |
Light from a distant galaxy can travel different paths to the earth because it is bent around an intermediary galaxy by what? | variation | radiation | strength | gravity | Figure 34.12 (a) Light from a distant galaxy can travel different paths to the Earth because it is bent around an intermediary galaxy by gravity. This produces several images of the more distant galaxy. (b) The images around the central galaxy are produced by gravitational lensing. Each image has the same spectrum and a larger red shift than the intermediary. (credit: NASA, ESA, and STScI). |
What is the fruiting body that occurs after two hyphae mate and form a mycelium with sporangia? | fungus | yeast | mold | mushroom | |
What branch of science aims to understand all about our planet and its environments? | petrology | biology | immunology | earth science | If someone asks you, “What is science?” you might say that it’s a bunch of facts and explanations. But that’s only part of the story. Science is a knowledge base. But science is also a way of learning about the world. Earth science is about our planet and its environments. Earth scientists study Earth’s surface and interior. They study why volcanoes erupt and why some places are mountainous and some are entirely flat. Some Earth scientists are interested in the weather. Others want to know about the oceans. There are even Earth scientists who apply what they know about Earth to learning about space. Some Earth scientists do a lot of their work in the field, as seen above. |
Prokaryotes are successful because of the ________ of reproduction in favorable environments | volume | order | cycle | speed | |
Where do benthos live in oceans? | In coral reefs | On the ocean surface | In deep water | on the ocean floor | Three main groups of ocean life are plankton, nekton, and benthos. Plankton float in the water. Nekton swim through the water. Benthos live on the ocean floor. |
Hundreds of organelles called myofibrils, made up of two types of protein filaments, are contained in each fiber of what? | cartilage | bone | hair | muscle | Each muscle fiber contains hundreds of organelles called myofibrils . Each myofibril is made up of two types of protein filaments: actin filaments, which are thinner, and myosin filaments, which are thicker. Actin filaments are anchored to structures called Z lines (see Figure below ). The region between two Z lines is called a sarcomere . Within a sarcomere, myosin filaments overlap the actin filaments. The myosin filaments have tiny structures called cross bridges that can attach to actin filaments. |
What is the largest known virus? | pneumonia virus | polyomavirus | influenza virus | mimivirus | The largest known virus, called mimivirus, is so large that scientists first mistook it for a bacterium. It was first discovered in amoeba, in 1992, and was identified as a virus in 2003. Scientists believe that mimivirus may cause certain types of pneumonia in humans. The core contains DNA, with the majority of the DNA in genes, and only 10% DNA of unknown function ("junk" DNA). |
The temperature at which something melts is refered to as what? | boiling point | precipitation point | evaporation point | melting point | Both of these people are participating in a board sport, but the man on the left is snowboarding in Norway while the woman on the right is sandboarding in Dubai. Snow and sand are both kinds of matter, but they have different properties. What are some ways snow and sand differ? One difference is the temperature at which they melt. Snow melts at 0°C, whereas sand melts at about 1600°C! The temperature at which something melts is its melting point. Melting point is just one of many physical properties of matter. |
Solid bedrock vibrates less and therefore does less of what to bedrock? | butress | block | dampen | damage | Ground type. Solid bedrock vibrates less than soft sediments, so there is less damage on bedrock. Sometimes sediments become saturated with water. They then undergo liquefaction and become like quicksand ( Figure below ). Soil on a hillside may become a landslide. |
What branch of science is defined as the study of matter? | biology | astrophysics | geology | chemistry | 1.8 End-of-Chapter Material Chapter Summary To ensure that you understand the material in this chapter, you should review the meanings of the bold terms in the following summary and ask yourself how they relate to the topics in the chapter. Chemistry is the study of matter, which is anything that has mass and takes up space. Chemistry is one branch of science, which is the study of the natural universe. Like all branches of science, chemistry relies on the scientific method, which is a process of Saylor URL: http://www. saylor. org/books. |
What are animals that live with tiny zooxanthellae that also photosynthesize? | fungi | worms | bacteria | coral | What's at the bottom of the food chain? A bit of the food energy comes from above, where plankton photosynthesize. Most comes from the coral. Coral are animals that live with tiny zooxanthellae that also photosynthesize. Of course, you know what's at the top of this food chain!. |
What usually causes fractures on a bone? | extra weight | compressive stress | shear stress | excessive bending stress | Even though they are very strong, bones can fracture , or break. Fractures can happen at different places on a bone. They are usually caused by excess bending stress on the bone. Bending stress is what causes a pencil to break if you bend it too far. |
What is the magnetic field traditionally referred to as? | spicule | m-field | charged field | bfield | 22.3 Magnetic Fields and Magnetic Field Lines Einstein is said to have been fascinated by a compass as a child, perhaps musing on how the needle felt a force without direct physical contact. His ability to think deeply and clearly about action at a distance, particularly for gravitational, electric, and magnetic forces, later enabled him to create his revolutionary theory of relativity. Since magnetic forces act at a distance, we define a magnetic field to represent magnetic forces. The pictorial representation of magnetic field lines is very useful in visualizing the strength and direction of the magnetic field. As shown in Figure 22.15, the direction of magnetic field lines is defined to be the direction in which the north end of a compass needle points. The magnetic field is traditionally called the Bfield. |
What can ultimately result when species are introduced to a new place and prey on other species? | elimination | depletion | over population | extinction | Humans have caused many extinctions by introducing species to new places. For example, many of New Zealand’s birds have adapted to nesting on the ground. This was possible because there were no land mammals in New Zealand. Then Europeans arrived and brought cats, foxes, and other predators with them. Several of New Zealand’s ground nesting birds, such as this flightless kiwi, are now extinct or threatened because of these predators. |
In humans, what is the first organ to form and become functional? | pancreas | brain | liver | heart | 19.5 Development of the Heart The heart is the first organ to form and become functional, emphasizing the importance of transport of material to and from the developing infant. It originates about day 18 or 19 from the mesoderm and begins beating and pumping blood about day 21 or 22. It forms from the cardiogenic region near the head and is visible as a prominent heart bulge on the surface of the embryo. Originally, it consists of a pair of strands called cardiogenic cords that quickly form a hollow lumen and are referred to as endocardial tubes. These then fuse into a single heart tube and differentiate into the truncus arteriosus, bulbus cordis, primitive ventricle, primitive atrium, and sinus venosus, starting about day 22. The primitive heart begins to form an S shape within the pericardium between days 23 and 28. The internal septa begin to form about day 28, separating the heart into the atria and ventricles, although the foramen ovale persists until shortly after birth. Between weeks five and eight, the atrioventricular valves form. The semilunar valves form between weeks five and nine. |
What is used to classify tornadoes? | humidity, rain | seismograph | damage, snowfall | wind speed, damage | The winds of a tornado can reach very high speeds. The faster the winds blow, the greater the damage they cause. Wind speed and damage are used to classify tornadoes. Table below shows how. |
What do you call materials that have high resistance to electric current? | destructive insulators | conductors | semiconductors | electric insulators | Materials that have high resistance to electric current are called electric insulators . Examples include most nonmetallic solids, such as wood, rubber, and plastic. Their atoms hold onto their electrons tightly, so electric current cannot flow freely through them. Dry air is also an electric insulator. You can learn more about electric insulators—as well as how to test whether a material is an insulator—by doing the activity at this URL:. |
What term is used to describe the development of new technology? | Smart Design | variation design | evident design | technological design | The development of new technology is called technological design . It is similar to scientific investigation. Both processes use evidence and logic to solve problems. |
Cell walls, plastids, and a large central vacuole distinguish plant cells from what? | eukaryotic cells | parenchyma cells | phloem cells | animal cells | 30.1 | The Plant Body By the end of this section, you will be able to: • Describe the shoot organ system and the root organ system • Distinguish between meristematic tissue and permanent tissue • Identify and describe the three regions where plant growth occurs • Summarize the roles of dermal tissue, vascular tissue, and ground tissue • Compare simple plant tissue with complex plant tissue Like animals, plants contain cells with organelles in which specific metabolic activities take place. Unlike animals, however, plants use energy from sunlight to form sugars during photosynthesis. In addition, plant cells have cell walls, plastids, and a large central vacuole: structures that are not found in animal cells. Each of these cellular structures plays a specific role in plant structure and function. |
Snails, scallops, and squids are what type of invertebrate? | arthropod | crustacean | algae | mollusk | Mollusks are invertebrates such as snails, scallops, and squids. They have a hard outer shell. There is a layer of tissue called the mantle between the shell and the body. Most mollusks have tentacles for feeding and sensing, and many have a muscular foot. Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion. The majority of mollusks live in the ocean. Different classes of mollusks have different ways of obtaining food. |
Humans create different breeds of organisms using what kind of selection? | natural selection | speciation | biased selection | artificial selection | Artificial Selection: Humans used artificial selection to create these different breeds. Both dog breeds are descended from the same wolves, and their genes are almost identical. |
The word antibiotic comes from the greek anti, meaning “against,” and bios, meaning this? | virus | bacteria | germ | life | The Antibiotic Crisis The word antibiotic comes from the Greek anti, meaning “against,” and bios, meaning “life. ” An antibiotic is an organismproduced chemical that is hostile to the growth of other organisms. Today’s news and media often address concerns about an antibiotic crisis. Are antibiotics that were used to treat bacterial infections easily treatable in the past becoming obsolete? Are there new “superbugs”—bacteria that have evolved to become more resistant to our arsenal of antibiotics? Is this the beginning of the end of antibiotics? All of these questions challenge the healthcare community. One of the main reasons for resistant bacteria is the overuse and incorrect use of antibiotics, such as not completing a full course of prescribed antibiotics. The incorrect use of an antibiotic results in the natural selection of resistant forms of bacteria. The antibiotic kills most of the infecting bacteria, and therefore only the resistant forms remain. These resistant forms reproduce, resulting in an increase in the proportion of resistant forms over non-resistant ones. Another problem is the excessive use of antibiotics in livestock. The routine use of antibiotics in animal feed promotes bacterial resistance as well. In the United States, 70 percent of the antibiotics produced are fed to animals. The antibiotics are not used to prevent disease, but to enhance production of their products. |
What are sudden and dramatic losses of biodiversity called? | normal extinction | explosive extinction | life extinction | mass extinction | Figure 21.13 Extinction intensity as reflected in the fossil record has fluctuated throughout Earth’s history. Sudden and dramatic losses of biodiversity, called mass extinctions, have occurred five times. |
The ions in ionic compounds are arranged in rigid three-dimensional patterns called what? | pattern lattices | core lattices | lattice groups | crystal lattices | The ions in ionic compounds are arranged in rigid three-dimensional patterns called crystal lattices. The crystal lattice that is formed is a characteristic property of a given compound. |
Where was the distinction between total distance traveled and displacement first noted? | string theory | uncertainty principle | Newton's first law | one-dimensional kinematics | Discussion Quite a trip (if it survives)! Note that this distance is the total distance traveled by the fly. Displacement is actually zero for complete revolutions because they bring the fly back to its original position. The distinction between total distance traveled and displacement was first noted in One-Dimensional Kinematics. |
What science is the study of the shape and arrangement of cells in tissue? | genetics | methodology | cellology | histology | CHAPTER REVIEW 4.1 Types of Tissues The human body contains more than 200 types of cells that can all be classified into four types of tissues: epithelial, connective, muscle, and nervous. Epithelial tissues act as coverings controlling the movement of materials across the surface. Connective tissue integrates the various parts of the body and provides support and protection to organs. Muscle tissue allows the body to move. Nervous tissues propagate information. The study of the shape and arrangement of cells in tissue is called histology. All cells and tissues in the body derive from three germ layers in the embryo: the ectoderm, mesoderm, and endoderm. Different types of tissues form membranes that enclose organs, provide a friction-free interaction between organs, and keep organs together. Synovial membranes are connective tissue membranes that protect and line the joints. Epithelial membranes are formed from epithelial tissue attached to a layer of connective tissue. There are three types of epithelial membranes: mucous, which contain glands; serous, which secrete fluid; and cutaneous which makes up the skin. |
What forms when a sperm fertilizes and egg? | proton | crystals | cytoplasm | zygote | |
The field of organic chemistry studies the structure and reactivity of compounds containing what element? | oxygen | nitrogen | hydrogen | carbon | Since then, the distinction between organic and inorganic compounds and reactions has blurred. Currently, the field of organic chemistry studies the structure and reactivity of nearly all carbon-containing compounds. Over twenty million organic compounds are known, ranging from very simple molecules to complex proteins. |
Where does growth in length occur, above the root cap? | apical meristem | primary tuber | vascular cambrium | primary meristem | As shown in Figure below , the tip of a root is called the root cap . It consists of specialized cells that help regulate primary growth of the root at the tip. Above the root cap is primary meristem, where growth in length occurs. |
Asci are used by mycelia for what kind of reproduction? | cloning | asexual reproduction | mitosis | sexual | hyphae divided by perforated septa, allowing streaming of cytoplasm from one cell to the other. Conidia and asci, which are used respectively for asexual and sexual reproductions, are usually separated from the vegetative hyphae by blocked (non-perforated) septa. Asexual reproduction is frequent and involves the production of conidiophores that release haploid conidiospores (Figure 24.13). Sexual reproduction starts with the development of special hyphae from either one of two types of mating strains (Figure 24.13). The “male” strain produces an antheridium and the “female” strain develops an ascogonium. At fertilization, the antheridium and the ascogonium combine in plasmogamy without nuclear fusion. Special ascogenous hyphae arise, in which pairs of nuclei migrate: one from the “male” strain and one from the “female” strain. In each ascus, two or more haploid ascospores fuse their nuclei in karyogamy. During sexual reproduction, thousands of asci fill a fruiting body called the ascocarp. The diploid nucleus gives rise to haploid nuclei by meiosis. The ascospores are then released, germinate, and form hyphae that are disseminated in the environment and start new mycelia (Figure 24.14). |
What is the term used to describe the liquid that moves through the vessels and includes plasma and the cells and sell fragments called platelets? | bacteria | water | pus | blood | 40.2 | Components of the Blood By the end of this section, you will be able to: • List the basic components of the blood • Compare red and white blood cells • Describe blood plasma and serum Hemoglobin is responsible for distributing oxygen, and to a lesser extent, carbon dioxide, throughout the circulatory systems of humans, vertebrates, and many invertebrates. The blood is more than the proteins, though. Blood is actually a term used to describe the liquid that moves through the vessels and includes plasma (the liquid portion, which contains water, proteins, salts, lipids, and glucose) and the cells (red and white cells) and cell fragments called platelets. Blood plasma is actually the dominant component of blood and contains the water, proteins, electrolytes, lipids, and glucose. The cells are responsible for carrying the gases (red cells) and immune the response (white). The platelets are responsible for blood clotting. Interstitial fluid that surrounds cells is separate from the blood, but in hemolymph, they are combined. In humans, cellular components make up approximately 45 percent of the blood and the liquid plasma 55 percent. Blood is 20 percent of a person’s extracellular fluid and eight percent of weight. |
The density of bone is, in part, related to the amount of what mineral in one’s diet? | nitrogen | potassium | barium | calcium | The densities of many components and products of the body have a bearing on our health. Bones. Bone density is important because bone tissue of lower-than-normal density is mechanically weaker and susceptible to breaking. The density of bone is, in part, related to the amount of calcium in one’s diet; people who have a diet deficient in calcium, which is an important component of bones, tend to have weaker bones. Dietary supplements or adding dairy products to the diet seems to help strengthen bones. As a group, women experience a decrease in bone density as they age. It has been estimated that fully half of women over age 50 suffer from excessive bone loss, a condition known as osteoporosis. Exact bone densities vary within the body, but for a healthy 30-year-old female, it is about 0.95–1.05 g/cm3. Osteoporosis is diagnosed if the bone density is below 0.6–0.7 g/cm3. Urine. The density of urine can be affected by a variety of medical conditions. Sufferers of diabetes insipidus produce an abnormally large volume of urine with a relatively low density. In another form of diabetes, called diabetes mellitus, there is excess glucose dissolved in the urine, so that the density of urine is abnormally high. The density of urine may also be abnormally high because of excess protein in the urine, which can be caused by congestive heart failure or certain renal (kidney) problems. Thus, a urine density test can provide clues to various kinds of health problems. The density of urine is commonly expressed as a specific gravity, which is a unitless quantity defined as. |
What is the sum of the masses of the atoms in a molecule? | atomic energy | compound mass | mass effect | molecular mass | Note: Atomic mass is given to three decimal places, if known. Now that we understand that atoms have mass, it is easy to extend the concept to the mass of molecules. The molecular mass is the sum of the masses of the atoms in a molecule. This may seem like a trivial extension of the concept, but it is important to count the number of each type of atom in the molecular formula. Also, although each atom in a molecule is a particular isotope, we use the weighted average, or atomic mass, for each atom in the molecule. For example, if we were to determine the molecular mass of dinitrogen trioxide, N2O3, we would need to add the atomic mass of nitrogen two times with the atomic mass of oxygen three times:. |
Chloroplasts, leucoplasts and chromoplasts are found in what type of cells? | man-made cells | nitrogen cells | animal cells | plant cells | A third difference between plant and animal cells is that plants have several kinds of organelles called plastids . And there are several different kinds of plastids in plant cells. For example, Chloroplasts are needed for photosynthesis, leucoplasts can store starch or oil, and brightly colored chromoplasts give some flowers and fruits their yellow, orange, or red color. It is the presence of chloroplasts and the ability to photosynthesize, that is one of the defining features of a plant. No animal or fungi can photosynthesize, and only some protists are able to. The photosynthetic protists are the plant-like protists, represented mainly by the unicellular algae. |
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