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Cartilage: There are three cartilage types: 1. hyaline cartilage 2. fibrocartilage (fibrous cartilage) 3. elastic cartilage Hyaline cartilage: most widespread cartilage type, in adults forms articular surfaces of long bones, rib tips, rings of trachea, and parts of skull. Mostly collagen, name refers to glassy appearance. In embryo, bones form first as hyaline cartilage, later ossifies. Found in tracheal rings. Few collagen fibers. Fibrous cartilage: have lots of collagen fibers. Found in intervertebral discs, pubic symphesis. Grades into dense tendon and ligament tissue. Elastic cartilage: springy and elastic. Found in internal support of external ear and in epiglottis, yellow when fresh. Chondrocites (cartilage cells) rely on diffusion for nutrients, as cartilage has no direct blood supply, and no enervation (nerves). Can be loaded with calcium salts.
Comprised mainly of collagen and associated with long bones and the skull, hyaline is the most widespread type of what? : collagen
Bacteria lack many of the structures that eukaryotic cells contain. For example, they don't have a nucleus. They also lack membrane-bound organelles, such as mitochondria or chloroplasts. The DNA of a bacterial cell is also different from a eukaryotic cell. Bacterial DNA is contained in one circular chromosome, located in the cytoplasm. Eukaryotes have several linear chromosomes. Bacteria also have two additional unique features: a cell wall and flagella.
Bacterial dna is contained in one circular chromosome, located where? : cytoplasm
Every surface has microscopic bumps, lumps, and imperfections, emphasized as in the image above. If we try to slide the top block over the lower block, there will be numerous collisions as the bumps impact each other. The forward motion causes the collisions with bumps which then exert a force in opposite way the block is moving. The force of friction always opposes whatever motion is causing the friction.
What force is caused by microscopic bumps, lumps, and imperfections colliding? : friction
The reproductive organs grow very slowly during childhood and do not mature until puberty. Puberty is the period during which humans become sexually mature. In the U. S. , boys generally begin puberty at about age 12 and complete it at about age 18.
What is the period during which humans become sexually mature called? : puberty
After birds lay their eggs, they generally keep the eggs warm with their body heat while the embryos inside continue to develop. This is called incubation, or brooding. In most species, parents stay together for at least the length of the breeding season. In some species, they stay together for life. By staying together, the males as well as females can incubate the eggs and later care for the hatchlings. Birds are the only nonhuman vertebrates with this level of male parental involvement.
What is another word for brooding- keeping eggs warm while the embryos develop? : incubation
Fires, which are a natural disturbance in temperate grasslands, can be ignited by lightning strikes. It also appears that the lightning-caused fire regime in North American grasslands was enhanced by intentional burning by humans. When fire is suppressed in temperate grasslands, the vegetation eventually converts to scrub and dense forests. Often, the restoration or.
Which type of natural disturbance in temperate grasslands, can be caused by a lightning strike? : fire
Mother of pearl is also known as nacre. Nacre is the iridescent inner shell layer. It can be found in buttons, watch faces, knives, guns, and jewelry. It is also used to decorate various musical instruments.
What is another name for mother of pearl? : nacre
Bile salts are secreted into the small intestine to aid in the digestion of fats.
What type of salts are secreted into the small intestine to aid in the digestion of fats? : bile
Oceanography is the study of the oceans. The word oceanology might be more accurate, since “ology” is “the study of. ” “Graph” is “to write” and refers to mapmaking. But mapping the oceans is how oceanography started.
What is oceanography the study of? : oceans
All waves are the way energy travels through matter. Ocean waves are energy traveling through water. They form when wind blows over the surface of the ocean. Wind energy is transferred to the sea surface. Then, the energy is carried through the water by the waves. Figure below shows ocean waves crashing against rocks on a shore. They pound away at the rocks and anything else they strike.
All waves are the way energy travels through what? : matter
Most living things use glucose for energy. The process in which glucose is made using light energy is photosynthesis. Water and carbon dioxide are needed for this process, and oxygen is produced as a byproduct. Photosynthetic organisms include plants, algae, and some bacteria.
What is the term for the process in which glucose is made using light energy? : photosynthesis
Life on Earth is based on carbon. A possible explanation is that no other element in the periodic table forms compounds that are so diverse in their chemistry and physical properties. Discuss the chemistry of carbon with regard to.
What element on the periodic table forms the most diverse compounds? : carbon
Calorimetry is the measurement of the transfer of heat into or out of a system during a chemical reaction or physical process. A calorimeter is an insulated container that is used to measure heat changes. The majority of reactions that can be analyzed in a calorimetry experiment are either liquids or aqueous solutions. A frequently used and inexpensive calorimeter is a set of nested foam cups fitted with a lid to limit the heat exchange between the liquid in the cup and the air in the surroundings (see Figure below ). In a typical calorimetry experiment, specific volumes of the reactants are dispensed into separate containers and the temperature of each is measured. They are then mixed into the calorimeter, which starts the reaction. The reactant mixture is stirred until the reaction is complete, while the temperature of the reaction is continuously monitored.
What kind of container is used to measure heat changes during a chemical reaction or physical process? : calorimeter
Ungulates include hoofed animals, such as deer, sheep, goats, pigs, buffalo, elephants and giraffes ( Figure below ). These mammals use their hoofs to sustain their whole body weight while moving. Hoofs are formed by a thick nail rolled around the tip of the toe.
In the mammal family, what is the name for hoofed animals, such as deer, sheep, goats, pigs, buffalo, elephants and giraffes? : ungulates
The plasma membrane may have extensions, such as whip-like flagella or brush-like cilia. In single-celled organisms, like those shown in Figure below , the membrane extensions may help the organisms move. In multicellular organisms, the extensions have other functions. For example, the cilia on human lung cells sweep foreign particles and mucus toward the mouth and nose.
In single-celled organisms, plasma membrane extensions, such as whip-like flagella or brush-like cilia, aid in what? : movement
Sperm are male gametes that form in the testes and mature in the epididymis.
What is defined as male gametes that form in the testes and mature in the epididymis? : sperm
To figure out how the solar system formed, we need to put together what we have learned. There are two other important features to consider. First, all the planets orbit in nearly the same flat, disk-like region. Second, all the planets orbit in the same direction around the Sun. These two features are clues to how the solar system formed.
All planets exhibit the same or nearly the same direction and shape of what path around the sun? : orbit
Mutations, a change in the DNA or RNA sequence, may have no effect, may be beneficial or may be harmful. There are numerous ways that the genetic information can be changed. Some of these changes can be inherited. In multicellular organisms, mutations can be subdivided into germline mutations , which can be passed on to descendants, and somatic mutations , which cannot be transmitted to the next generation. Germline mutations change the DNA sequence within a sperm or egg cell, and therefore can be inherited. This inherited mutation may result in a class of diseases known as a genetic disease. The mutation may lead to a nonfunctional protein, and the embryo may not develop properly or survive. Somatic mutations may affect the proper functioning of the cell with the mutation. During DNA replication, the mutation will be copied. The two daughter cells formed after cell division will both carry the mutation. This may lead to the development of many cells that do not function optimally, resulting a less than optimal phenotype. Various types of mutations can all have severe effects on the individual. These include point mutations, framehift mutations and chromosomal alterations. Keep in mind, some mutations may be beneficial or have no effect. Mutations that have no effect will not affect the expression of the gene or the sequence of amino acids in an encoded protein.
What do you call a change in the dna or rna sequence? : mutation
Hydrogen gas and oxygen gas are ignited to produce water.
What is produced when hydrogen gas and oxygen gas are ignited? : water
Migration is the movement of animals from one place to another. Migration is most common in birds, fish, and insects. In the Northern Hemisphere, many species of birds, such as finches and swallows, travel south for the winter. They migrate to areas where it is warmer and where more food is available. They return north in the spring. Migrating animals generally follow the same route each year. They may be guided by the position of the sun, Earth’s magnetic field, or other clues in the environment.
What is the movement of animals from one place to another called? : migration
The job of the respiratory system is the exchange of gases between the body and the outside air. This process, called respiration , actually consists of two parts. In the first part, oxygen in the air is drawn into the body and carbon dioxide is released from the body through the respiratory tract. In the second part, the circulatory system delivers the oxygen to body cells and picks up carbon dioxide from the cells in return. The lungs are organs of the respiratory system. It is in the lungs where oxygen is transferred from the respiratory system to the circulatory system.
What does the respiratory system exchange between the body and the outside air? : gases
The volume of a regularly shaped solid can be calculated from its dimensions. For example, the volume of a rectangular solid is the product of its length, width, and height.
The volume of a regularly shaped solid can be calculated from its what? : dimensions
Systemic communication through the phloem helps integrate the functions of the whole what? : plant
Oil is a thick, dark brown or black liquid. It is found in rock layers of Earth's crust. Oil is currently the most commonly used source of energy in the world.
What is a thick, dark brown or black liquid found in rock layers of the earth's crust? : oil
Atoms are indestructible and constantly in motion.
What are indestructible and constantly in motion? : atoms
What part of a plant protects the plant cell, maintains its shape, and prevents excessive uptake of water? : wall
Nuclear power is clean. It does not pollute the air. However, the use of nuclear energy does create other environmental problems. Uranium must be mined ( Figure below ). The process of splitting atoms creates radioactive waste. This waste may be dangerous for thousands or hundreds of thousands of years. As yet, there is no long-term solution for storing the radioactive waste.
The process of splitting atoms creates what kind of waste? : radioactive
Sometimes atoms lose or gain electrons. Then they become ions . Ions have a positive or negative charge. That’s because they do not have the same number of electrons as protons. If atoms lose electrons, they become positive ions, or cations. If atoms gain electrons, they become negative ions, or anions.
When an atom gains or loses an electron it becames an? : ion
Although this cartoon pokes fun at scientific hypotheses, the concept of hypothesis is one of the most important in science. Scientific investigations discover evidence that helps science advance, and the purpose of scientific investigations generally is to test hypotheses. Finding evidence to support or disprove hypotheses is how science advances.
The purpose of scientific investigations generally is to test a what? : hypothesis
Reflecting surfaces do not have to be flat. The most common curved mirrors are spherical. A spherical mirror is called a concave mirror if the center of the mirror is further from the viewer than the edges are. A spherical mirror is called a convex mirror if the center of the mirror is closer to the viewer than the edges are.
The most common curved mirrors are what? : spherical
The three types of plant cells are found in each of the major types of plant tissues: dermal, ground, and vascular tissues. Dermal tissue covers the outside of a plant in a single layer of cells called the epidermis. It mediates most of the interactions between a plant and its environment. Ground tissue makes up most of the interior of a plant. It carries out basic metabolic functions and stores food and water. Vascular tissue runs through the ground tissue inside a plant. It consists of bundles of xylem and phloem, which transport fluids throughout the plant.
What type of tissue covers the outside of a plant in a single layer of cells called the epidermis? : dermal
The electron loss and gain is easy to see in a reaction in which ions are formed. However, in many reactions, no such electron transfer occurs. In a molecular compound, electrons are shared between atoms in a type of bond called a covalent bond. Yet it is still common for reactions involving molecular compounds to still be classified as redox reactions.
In a molecular compound, electrons are shared between atoms in which type of bond? : covalent
Minerals form from dissolved substances when water evaporates.
What process does water undergo to leave behind dissolved substances? : evaporation
Proteins play many important roles in living things. Some proteins help cells keep their shape, and some make up muscle tissues. Many proteins speed up chemical reactions in cells. Other proteins are antibodies, which bind to foreign substances such as bacteria and target them for destruction. Still other proteins carry messages or materials. For example, human red blood cells contain a protein called hemoglobin, which binds with oxygen. Hemoglobin allows the blood to carry oxygen from the lungs to cells throughout the body. A model of the hemoglobin molecule is shown in Figure below .
What type of proteins bind to foreign substances and attempt destruction? : antibodies
8.2 | The Light-Dependent Reactions of Photosynthesis By the end of this section, you will be able to: • Explain how plants absorb energy from sunlight • Describe short and long wavelengths of light • Describe how and where photosynthesis takes place within a plant How can light be used to make food? When a person turns on a lamp, electrical energy becomes light energy. Like all other forms of kinetic energy, light can travel, change form, and be harnessed to do work. In the case of photosynthesis, light energy is converted into chemical energy, which photoautotrophs use to build carbohydrate molecules (Figure 8.9). However, autotrophs only use a few specific components of sunlight.
Photosynthesis involves reactions that are dependent on what? : light
Like simple hormone pathways, hormone cascade pathways typically involve what kind of feedback? : negative
The ocean basin begins where the ocean meets the land. The continental margin begins at the shore and goes down to the ocean floor. It includes the continental shelf, slope, and rise. The continental shelf is part of the continent, but it is underwater today. It is about 100-200 meters deep, much shallower than the rest of the ocean. The continental shelf usually goes out about 100 to 200 kilometers from the shore ( Figure below ).
The ocean basin begins where the ocean meets what? : land
Immunity can be acquired in an active or passive way, and it can be natural or artificial. Watch this video (http://openstaxcollege. org/l/immunity) to see an animated discussion of passive and active immunity. What is an example of natural immunity acquired passively?.
What bodily defense can be acquired in an active or passive way, and can be natural or artificial? : immunity
Like the stem, the leaf contains vascular bundles composed of xylem and phloem (Figure 30.27). The xylem consists of tracheids and vessels, which transport water and minerals to the leaves. The phloem transports the photosynthetic products from the leaf to the other parts of the plant. A single vascular bundle, no matter how large or small, always contains both xylem and phloem tissues.
Like the stem, what basic plant structure contains vascular bundles composed of xylem and phloem? : leaf
What kind of symmetry do echinoderm larvae have? : bilateral
Epidemiologist Epidemiology is the study of the occurrence, distribution, and determinants of health and disease in a population. It is, therefore, part of public health. An epidemiologist studies the frequency and distribution of diseases within human populations and environments. Epidemiologists collect data about a particular disease and track its spread to identify the original mode of transmission. They sometimes work in close collaboration with historians to try to understand the way a disease evolved geographically and over time, tracking the natural history of pathogens. They gather information from clinical records, patient interviews, surveillance, and any other available means. That information is used to develop strategies, such as vaccinations (Figure 22.26), and design public health policies to reduce the incidence of a disease or to prevent its spread. Epidemiologists also conduct rapid investigations in case of an outbreak to recommend immediate measures to control it. An epidemiologist has a bachelor’s degree, plus a master’s degree in public health (MPH). Many epidemiologists are also physicians (and have an M. ), or they have a Ph. in an associated field, such as biology or microbiology.
What is a person who studies the frequency and distribution of disease within human populations and environments called? : epidemiologist
In some cases, a population of one species disperses throughout an area, and each finds a distinct niche or isolated habitat. Over time, the varied demands of their new lifestyles lead to multiple speciation events originating from a single species, which is called adaptive radiation. From one point of origin, many adaptations evolve causing the species to radiate into several new ones. Island archipelagos like the Hawaiian Islands provide an ideal context for adaptive radiation events because water surrounds each island, which leads to geographical isolation for many organisms (Figure 11.16). The Hawaiian honeycreeper illustrates one example of adaptive radiation. From a single species, called the founder species, numerous species have evolved, including the eight shown in Figure 11.16.
In adaptive radiation, what is the name of the initial species that then subsequently becomes multiple other ones? : founder
The structures of both trifluoramine and hydroxylamine are similar to that of ammonia.
The structures of both trifluoramine and hydroxylamine are similar to that of what? : ammonia
Reptiles also have several adaptations for living on land. They have a skin covered in scales to protect them from drying out. All reptiles have lungs to breathe air. Reptiles are also amniotes , which means their embryos are surrounded by a thin membrane. This membrane protects the embryo from the harsh conditions of living on land. Reptile eggs are also surrounded by a protective shell, which may be either flexible or inflexible.
What protects reptiles from drying out? : scales
Have you ever eaten blue cheese? Do you know what makes it blue? You guessed it. A fungus. For certain types of cheeses, producers add fungal spores to milk curds to promote the growth of mold, which makes the cheese blue. Molds used in cheese production are safe for humans to eat.
What makes blue cheese blue? : fungus
Coevolution often happens in species that have symbiotic relationships. Examples include flowering plants and their pollinators.
What type of evolution often happens in species that have symbiotic relationships? : coevolution
Helicopter pilots are quite familiar with rotational kinetic energy. They know, for example, that a point of no return will be reached if they allow their blades to slow below a critical angular velocity during flight. The blades lose lift, and it is impossible to immediately get the blades spinning fast enough to regain it. Rotational kinetic energy must be supplied to the blades to get them to rotate faster, and enough energy cannot be supplied in time to avoid a crash. Because of weight limitations, helicopter engines are too small to supply both the energy needed for lift and to replenish the rotational kinetic energy of the blades once they have slowed down. The rotational kinetic energy is put into them before takeoff and must not be allowed to drop below this crucial level. One possible way to avoid a crash is to use the gravitational potential energy of the helicopter to replenish the rotational kinetic energy of the blades by losing altitude and aligning the blades so that the helicopter is spun up in the descent. Of course, if the helicopter’s altitude is too low, then there is insufficient time for the blade to regain lift before reaching the ground. Problem-Solving Strategy for Rotational Energy 1. Determine that energy or work is involved in the rotation. Determine the system of interest. A sketch usually helps. Analyze the situation to determine the types of work and energy involved. For closed systems, mechanical energy is conserved. That is,.
Helicopter pilots can recover from piloting errors by decreasing altitude, turning some of their potential energy into what kind of energy? : kinetic
Carrying this one step further, we note that the slope of a velocity versus time graph is acceleration. Slope is rise divided by run; on a v vs. t graph, rise = change in velocity Δv and run = change in time Δt . The Slope of v vs. t The slope of a graph of velocity.
Rise divided by run is called what? : slope
Sometimes cancer cells break away from a tumor. If they enter the bloodstream, they are carried throughout the body. Then, the cells may start growing in other tissues. This is usually how cancer spreads from one part of the body to another. Once this happens, cancer is very hard to stop or control.
How do cancer cells typically spread from one part of the body to another? : bloodstream
would not be surprised if the surviving populations experienced serious bottlenecks. The subsequent diversification of the surviving organisms, such as the Dinosauria (which includes the extinct dinosaurs and modern birds) and the Cynodontia, which includes the ancestors of modern mammals, including us, could be due in part to these bottleneck-associated effects, for example, through the removal of competing species or predators. An astreroid impact, known as the Cretaceous-Tertiary event, occurred ~65 million years ago; it contributed to the extinction of the dinosaurs and led to the diversification of mammals (which had first appeared in the fossil record ~160 million years ago). While surviving an asteroid impact (or other dramatic changes in climate) may be random, in other cases who survives a bottleneck is not. Consider the effects of a severe drought or highly virulent bacterial or viral infection; the organisms that survive may have specific phenotypes (and associated genotypes) that significantly influence their chance of survival. In such a case, the effect of the bottleneck event would produce non-random changes in the distribution of genotypes (and alleles) in the post-bottleneck population – these selective effects could continue to influence the population in various ways. For example, a trait associated with pathogen resistance may also have negative phenotypic effects. After the pathogen-driven bottleneck, mutations that mitigate the resistance trait's negative effects (and may have their own effects) can be selected. The end result is that traits that would not be selected in the absence of the pathogen, are selected. In addition, the very occurrence of a rapid and extreme reduction in population size has its own effects. For example, it would be expected to increase the effects of genetic drift (see below) and could make finding a mate more difficult. We can identify extreme population reduction events, such as founder effects and bottlenecks, by looking at the variation in genotypes (that is, the sequence of DNA molecules), particularly in genotypic changes not expected to influence phenotypes, mating preference, or reproductive success. These so-called neutral polymorphisms are expected to accumulate in the regions of the genome between genes (intragenic regions) at a constant rate over time (can you suggest why?) The rate of the accumulation of neutral polymorphisms serves as a type of population-based biological clock. Its rate can be estimated, at least roughly, by comparing the genotypes of individuals of different populations whose time of separation can be accurately estimated (assuming of course that there has been no migrations between the populations). Such studies of genomic sequence data (which we will return to later in much greater detail) indicate that the human population arose in Africa ~500,000 years ago. 119 Before this, the population leading to humans is thought to have undergone a bottleneck around ~1.2 million years ago.120 Once established, groups of modern humans migrated within and out of African, undergoing a series of founder effect events between ~45,000 to 60,000 years ago first as they migrated from southern Africa into the regions of the Horn of Africa, then into the Arabian peninsula, and from there into Europe, Asia, Oceania, and finally the Americas. (↓) Comparing genotypes, that is, neutral polymorphisms, between 119.
The rate of the accumulation of neutral what serves as a type of population-based biological clock? : polymorphisms
The transmitted light strikes a photoelectric tube, which converts the light energy to? : electricity
An atom is the smallest unit of a chemical element . That is, an atom has all the properties of that element. All atoms of the same element have the same number of protons.
What is the smallest unit of a chemical element called? : atom
One dimensional motion describes objects moving in straight lines. Speed is a scalar measure of how quickly an object is moving along this line. Velocity is speed with a direction, making it a vector. If an object’s velocity changes with time, the object is said to be accelerating. When restricted to one dimension, there are only two possible directions for the velocity and acceleration vectors to point in. As we’ll see in the next chapters, understanding an object's acceleration is the key to understanding its motion.
What is the term for a scalar measure of how quickly an object is moving along this line? : speed
A combination reaction makes a new substance from more than one reactant; a redox reaction rearranges electrons. Not all combination reactions are redox reactions, and not all redox reactions are combination reactions.
A redox reaction rearranges what subatomic particles? : electrons
Ingestive protists ingest, or engulf, bacteria and other small particles. They extend their cell wall and cell membrane around the food item, forming a food vacuole. Then enzymes digest the food in the vacuole.
What substances digest the food in the vacuole of an ingestive protist? : enzymes
The speed of sound also depends on the temperature of the medium. For a given medium such as air, sound has a slower speed at lower temperatures. You can compare the speed of sound in air at different temperatures in Table below . A lower temperature means that particles of the medium are moving more slowly, so it takes them longer to transfer the energy of the sound waves. The amount of water vapor in the air affects the speed of sound as well. Do you think sound travels faster or slower when the air contains more water vapor? ( Hint: Compare the speed of sound in water and air in Table above . ).
The amount of water vapor in the air and the temperature of the medium affects how fast what travels? : sound
This chart shows the genetic code used by all organisms. For example, an RNA codon reading GUU would encode for a valine (Val) according to this chart. Start at the center for the first base of the three base codon, and work your way out. Notice that more than one codon may encode for a single amino acid. For example, glycine (Gly) is encoded by a GGG, GGA, GGC, and GGU. Notice there are 64 codons. Of the 64 codons, three are stop codons.
An rna codon reading guu encodes for what? : valine
Reptiles are a class of ectothermic, tetrapod vertebrates. They have several adaptations for living on dry land, such as tough keratin scales and efficient lungs for breathing air. They also have a three-chambered heart and relatively well-developed brain.
How many chambers are in a reptiles heart? : three
The pupil is an opening in the front of the eye. It looks black because it doesn’t reflect any light. All the light passes through it instead. The pupil controls the amount of light that enters the eye. It automatically gets bigger or smaller to let more or less light in as needed.
What is the opening in the front of the eye called? : pupil
Water density increases as salinity and pressure increase, or as temperature decreases.
When salinity and pressure increase, or when temperature decreases, what happens to water density? : increases
contain the carbonyl functional group (C=O; part (a) in Figure 24.14 "The Oxidation State of Carbon in Oxygen- and Nitrogen-Containing Functional Groups"). Alcohols are classified as primary, secondary, or tertiary, depending on whether the –OH group is bonded to a primary, secondary, or tertiary carbon. For example, the compound 5-methyl-3-hexanol is a secondary alcohol.
The bending of a wave around the edges of an opening or an obstacle is called this? : diffraction
What is the process by which plants make their own food called? : photosynthesis
Strategy: A Based on the conductivity of the elements, determine whether each is a metal, a nonmetal, or a semimetal. Confirm your prediction from its physical appearance. B From the compounds each element forms, determine its common oxidation states. C If the element is a nonmetal, it must be located in the p block of the periodic table. If a semimetal, it must lie along the diagonal line of semimetals from B to At. Transition metals can have two oxidation states separated by one electron. D From your classification, the oxidation states of the element, and its physical appearance, deduce its identity. Solution:.
Conductivity, oxidation state and physical appearance are properties that help determine whether what are metals? : elements
The endocrine system consists of glands that secrete hormones into the bloodstream. It is regulated by a part of the brain called the hypothalamus, which also secretes hormones. The hypothalamus controls the pituitary gland, which is called the “master gland” of the endocrine system because its hormones regulate other endocrine glands. Other endocrine glands include the thyroid gland and pancreas.
What specific part of the brain regulates the endocrine system? : hypothalamus
Chemical reactions follow the laws of thermodynamics. The First Law of Thermodynamics states that energy can be changed from one form to another, but it cannot be created or destroyed. This law is also known as the Law of Conservation of Energy. The Second Law of Thermodynamics states the energy available after a chemical reaction is always less than that at the beginning of a reaction. This is also commonly referred to as entropy. Entropy can be described as the degree of disorder in a system . That is, as energy is transferred from one form to another, some of the energy is lost as heat, and the amount of available energy decreases. As the energy decreases, the disorder in the system increases, and, by definition, the entropy increases. Ice melting provides an example in which entropy increases. Entropy essentially is a measure of the tendency of a process, such as a chemical reaction, to proceed in a particular direction.
Chemical reactions follow which laws? : thermodynamics
CHAPTER SUMMARY 37.1 Types of Hormones There are three basic types of hormones: lipid-derived, amino acid-derived, and peptide. Lipid-derived hormones are structurally similar to cholesterol and include steroid hormones such as estradiol and testosterone. Amino acid-derived hormones are relatively small molecules and include the adrenal hormones epinephrine and norepinephrine. Peptide hormones are polypeptide chains or proteins and include the pituitary hormones, antidiuretic hormone (vasopressin), and oxytocin.
There are three basic types of hormones: lipid-derived, amino acid-derived, and what? : peptide
Fertilization occurs when an egg and sperm come together to form a zygote.
Fertilization occurs when an egg and sperm come together to form a what? : zygote
The explosion of nitroglycerin releases large volumes of gases and is very exothermic.
The explosion of nitroglycerin, which releases large volumes of gases, is what type of reaction? : exothermic
Carbohydrates include sugars, starches, and fiber. Sugars and starches are used by the body for energy. One gram of carbohydrates provides 4 Calories of energy. Fiber, which is found in plant foods, cannot be digested but is needed for good health. Simple carbohydrates are small carbohydrates found in foods such as fruits and milk. These carbohydrates include lactose, fructose and glucose. Complex carbohydrates are much larger molecules. Starch, which is a complex carbohydrate found in vegetables and grains, is made of thousands of glucose units bonded together.
What category of food includes sugars, starches and fibers? : carbohydrates
Nutrients are substances that the body needs for energy, building materials, and control of body processes. Carbohydrates, proteins, lipids, and water are nutrients needed in relatively large amounts. Vitamins and minerals are nutrients needed in much smaller amounts.
What are substances that the body needs for energy, building materials, and control of body processes? : nutrients
When plants reproduce, the offspring has characteristics similar to the? : parents
Algae are like plants mainly because they contain chloroplasts. This allows them to make food by photosynthesis. Algae are important producers in water-based ecosystems such as the ocean. On the other hand, algae lack other plant structures. For example, they don’t have roots, stems, or leaves. Also unlike plants, some algae can move. They may move with pseudopods or flagella.
Algae are like plants mainly because they contain what? : chloroplasts
Mutations have many possible causes. Some mutations occur when a mistake is made during DNA replication or transcription. Other mutations occur because of environmental factors. Anything in the environment that causes a mutation is known as a mutagen . Examples of mutagens are shown in Figure below . They include ultraviolet rays in sunlight, chemicals in cigarette smoke, and certain viruses and bacteria.
What is it called when a mistake occurs in dna replication. : mutation
The mostly subterranean lifestyle of stone plants reduces water loss from evaporation and inhibits what? : photosynthesis
During the Permian Period, all the major landmasses moved together to form one supercontinent. The supercontinent has been named Pangaea. You can see how it looked in Figure below . At this time, temperatures were extreme and the climate became very dry. As a result, plants and animals evolved ways to cope with dryness. For example, reptiles evolved leathery skin. This helped prevent water loss. Plants evolved waxy leaves for the same purpose.
All the major landmasses moved together to form one supercontinent in which period? : permian
Engineering is the practical application of scientific principles and discoveries to develop things that make our lives easier. Is medicine science or engineering? Justify your answer.
What is the practical application of scientific principles and discoveries to develop things that make our lives easier? : engineering
A composite volcano forms the tall cone shape you usually think of when you think of a volcano. Shield volcanoes are huge, gently sloping volcanoes. Cinder cones are small, cone-shaped volcanoes.
What is the type of volcano with a tall cone shape that you picture when picturing a volcano? : composite
In many species, including humans, circadian rhythms are controlled by a tiny structure called the biological clock . This structure is located in a gland at the base of the brain. The biological clock sends signals to the body. The signals cause regular changes in behavior and body processes. The amount of light entering the eyes helps control the biological clock. The clock causes changes that repeat every 24 hours.
The amount of what entering the eyes helps control the biological clock? : light
Glial Cells of the PNS One of the two types of glial cells found in the PNS is the satellite cell. Satellite cells are found in sensory and autonomic ganglia, where they surround the cell bodies of neurons. This accounts for the name, based on their appearance under the microscope. They provide support, performing similar functions in the periphery as astrocytes do in the CNS—except, of course, for establishing the BBB. The second type of glial cell is the Schwann cell, which insulate axons with myelin in the periphery. Schwann cells are different than oligodendrocytes, in that a Schwann cell wraps around a portion of only one axon segment and no others. Oligodendrocytes have processes that reach out to multiple axon segments, whereas the entire Schwann cell surrounds just one axon segment. The nucleus and cytoplasm of the Schwann cell are on the edge of the myelin sheath. The relationship of these two types of glial cells to ganglia and nerves in the PNS is seen in Figure 12.12.
Satellite and schwann cells are the two types of what kind of cell found in the pns? : glial
Ionic compounds have positive ions and negative ions.
What compound has positive and negative ions? : ionic
Mole-mole calculations are not the only type of calculations that can be performed using balanced chemical equations. Recall that the molar mass can be determined from a chemical formula and used as a conversion factor. We can add that conversion factor as another step in a calculation to make a molemass calculation, where we start with a given number of moles of a substance and calculate the mass of another substance involved in the chemical equation, or vice versa. For example, suppose we have the balanced chemical equation.
What effect, related to weather forecasting, occurs not only for sound but for any wave when there is relative motion between the observer and the source? : doppler
science of heredity, or how traits are passed from parents to offspring.
What is the science of how traits are passed from parents to offspring? : heredity
which is identical to the Rydberg equation for R ∞ = k . When Bohr calculated his theoretical value for the hc Rydberg constant, R ∞, and compared it with the experimentally accepted value, he got excellent agreement. Since the Rydberg constant was one of the most precisely measured constants at that time, this level of agreement was astonishing and meant that Bohr’s model was taken seriously, despite the many assumptions that Bohr needed to derive it. The lowest few energy levels are shown in Figure 6.14. One of the fundamental laws of physics is that matter is most stable with the lowest possible energy. Thus, the electron in a hydrogen atom usually moves in the n = 1 orbit, the orbit in which it has the lowest energy. When the electron is in this lowest energy orbit, the atom is said to be in its ground electronic state (or simply ground state). If the atom receives energy from an outside source, it is possible for the electron to move to an orbit with a higher n value and the atom is now in an excited electronic state (or simply an excited state) with a higher energy. When an electron transitions from an excited state (higher energy orbit) to a less excited state, or ground state, the difference in energy is emitted as a photon. Similarly, if a photon is absorbed by an atom, the energy of the photon moves an electron from a lower energy orbit up to a more excited one. We can relate the energy of electrons in atoms to what we learned previously about energy. The law of conservation of energy says that we can neither create nor destroy energy. Thus, if a certain amount of external energy is required to excite an electron from one energy level to another, that same amount of energy will be liberated when the electron returns to its initial state (Figure 6.15). In effect, an atom can “store” energy by using it to promote an electron to a state with a higher energy and release it when the electron returns to a lower state. The energy can be released as one quantum of energy, as the electron returns to its ground state (say, from n = 5 to n = 1), or it can be released as two or more smaller quanta as the electron falls to an intermediate state, then to the ground state (say, from n = 5 to n = 4, emitting one quantum, then to n = 1, emitting a second quantum). Since Bohr’s model involved only a single electron, it could also be applied to the single electron ions He+, Li2+, Be3+, and so forth, which differ from hydrogen only in their nuclear charges, and so one-electron atoms and ions are collectively referred to as hydrogen-like atoms. The energy expression for hydrogen-like atoms is a generalization of the hydrogen atom energy, in which Z is the nuclear charge (+1 for hydrogen, +2 for He, +3 for Li, and so on) and k has a value of 2.179 × 10–18 J. E n = − kZ2 n.
When an electron transitions from an excited state to a less excited state, or ground state, the difference in energy is emitted as a what? : photon
Figure 46.14 Water from the land and oceans enters the atmosphere by evaporation or sublimation, where it condenses into clouds and falls as rain or snow. Precipitated water may enter freshwater bodies or infiltrate the soil. The cycle is complete when surface or groundwater reenters the ocean. (credit: modification of work by John M. Evans and Howard Perlman, USGS).
Water from the land and oceans enters the atmosphere by which process? : evaporation
Rising and sinking air can influence the precipitation of a region.
What does rising and sinking air influence in a region? : precipitation
Refracting and reflecting telescopes are optical telescopes that use lenses to gather light.
Refracting and reflecting telescopes are optical telescopes that use lenses to gather what? : light
Via what process do substance move from one cell to another? : plasmodesmata
Levels of organization, from the atom (smallest) to the organism (largest). Notice that organelles are inside a cell, and organs are inside an organism.
What is the largest level of organization? : organism
Living species of chordates are classified into three major subphyla: Vertebrata, Urochordata, and Cephalochordata. Vertebrates are all chordates that have a backbone. The other two subphyla are invertebrate chordates that lack a backbone.
Living species of chordates are classified into three major subphyla: vertebrata, urochordata, and what? : cephalochordata
Tennis is played on a variety of court surfaces: grass, clay, hardcourt, and even carpet. Players know that matches on different surfaces are distinctly different games. The ball bounces differently, and shoes slip on some surfaces but stick on others. These differences are a result of friction.
What force explains why a tennis ball bounces differently on different surfaces, and shoes slip on some surfaces but stick on others? : friction
The cavities normally contain hydrated cations that are loosely bound to the oxygen atoms of the negatively charged framework by electrostatic interactions. The sizes and arrangements of the channels and cavities differ in different types of zeolites. For example, in zeolite A the aluminosilicate cages are arranged in a cubic fashion, and the channels connecting the cavities intersect at right angles. In contrast, the cavities in faujasite are much larger, and the channels intersect at 120° angles. In these idealized models, the oxygen atoms that connect each pair of silicon atoms have been omitted. Silicon and germanium react with nitrogen at high temperature to form nitrides(M3N4): Equation 22.26.
Silicon and germanium react with nitrogen at high temperature to form what? : nitrides
An ionic bond is the force of attraction that holds together oppositely charged ions. It forms when atoms of a metal transfer electrons to atoms of a nonmetal. When this happens, the atoms become oppositely charged ions.
What bond is the force of attraction that holds together oppositely charged ions? : ionic
Some of the most important animal behaviors involve mating. Mating is the pairing of an adult male and female to produce young. Adults that are most successful at attracting a mate are most likely to have offspring. Traits that help animals attract a mate and have offspring increase their fitness. As the genes that encode these traits are passed to the next generation, the traits will become more common in the population.
What is the pairing of an adult male to an adult female to produce young? : mating
3.6 Active Transport The combined gradient that affects an ion includes its concentration gradient and its electrical gradient. Living cells need certain substances in concentrations greater than they exist in the extracellular space. Moving substances up their electrochemical gradients requires energy from the cell. Active transport uses energy stored in ATP to fuel the transport. Active transport of small molecular-size material uses integral proteins in the cell membrane to move the material—these proteins are analogous to pumps. Some pumps, which carry out primary active transport, couple directly with ATP to drive their action. In secondary transport, energy from primary transport can be used to move another substance into the cell and up its concentration gradient. Endocytosis methods require the direct use of ATP to fuel the transport of large particles such as macromolecules; parts of cells or whole cells can be engulfed by other cells in a process called phagocytosis. In phagocytosis, a portion of the membrane invaginates and flows around the particle, eventually pinching off and leaving the particle wholly enclosed by an envelope of plasma membrane. Vacuoles are broken down by the cell, with the particles used as food or dispatched in some other way. Pinocytosis is a similar process on a smaller scale. The cell expels waste and other particles through the reverse process, exocytosis. Wastes are moved outside the cell, pushing a membranous vesicle to the plasma membrane, allowing the vesicle to fuse with the membrane and incorporating itself into the membrane structure, releasing its contents to the exterior of the cell.
The cell expels waste and other particles through a process called what? : exocytosis
The skin consists of two distinct layers, an outer layer called the epidermis and an inner layer called the dermis. The epidermis is constantly being renewed as dead cells on the surface are shed. This layer contains melanin-producing melanocytes. The dermis contains blood vessels, nerve endings, hair follicles, and sebaceous and sweat glands.
Shedding of dead cells ensures constant renewal of what outer layer of the skin? : epidermis
Droughts also depend on what is normal for a region. A region that gets significantly less precipitation than normal for an extended period of time is in drought. The Southern United States is experiencing an ongoing and prolonged drought.
What term is used to describe a region getting significantly less precipitation than normal for an extended period of time? : drought
The fuel that burns in a combustion reaction contains compounds called hydrocarbons. Hydrocarbons are compounds that contain only carbon (C) and hydrogen (H). The charcoal pictured in the Figure above consists of hydrocarbons. So do fossil fuels such as natural gas. Natural gas is a fuel that is commonly used in home furnaces and gas stoves. The main component of natural gas is the hydrocarbon called methane (CH 4 ). You can see a methane flame in the Figure below . The combustion of methane is represented by the equation:.
What is the name for compounds that contain only carbon and hydrogen? : hydrocarbons
untreated, it produces severe brain damage and mental retardation. Albinism is caused by a defective enzyme that is unable to produce melanin, the pigment responsible for the color of skin and hair. Cystic fibrosis, the most common inherited disease in the United States, blocks pancreatic function and causes thick mucus secretions that make breathing difficult. An area of intense research in combating cancer involves the synthesis of drugs that stop uncontrolled cell growth by interfering with DNA replication.
What human disease is caused by a defective enzyme that is unable to produce melanin, the pigment responsible for the color of skin and hair? : albinism
Cartilage Templates Bone is a replacement tissue; that is, it uses a model tissue on which to lay down its mineral matrix. For skeletal development, the most common template is cartilage. During fetal development, a framework is laid down that determines where bones will form. This framework is a flexible, semi-solid matrix produced by chondroblasts and consists of hyaluronic acid, chondroitin sulfate, collagen fibers, and water. As the matrix surrounds and isolates chondroblasts, they are called chondrocytes. Unlike most connective tissues, cartilage is avascular, meaning that it has no blood vessels supplying nutrients and removing metabolic wastes. All of these functions are carried on by diffusion through the matrix. This is why damaged cartilage does not repair itself as readily as most tissues do. Throughout fetal development and into childhood growth and development, bone forms on the cartilaginous matrix. By the time a fetus is born, most of the cartilage has been replaced with bone. Some additional cartilage will be replaced throughout childhood, and some cartilage remains in the adult skeleton.
For skeletal development, the most common template is what? : cartilage
The body's second line of defense against pathogens includes the inflammatory response. If bacteria enter the skin through a scrape, the area may become red, warm, and painful. These are signs of inflammation. Inflammation is one way the body reacts to infections or injuries. Inflammation is caused by chemicals that are released when skin or other tissues are damaged. The chemicals cause nearby blood vessels to dilate, or expand. This increases blood flow to the damaged area, which makes the area red and slightly warm. The chemicals also attract white blood cells called neutrophils to the wound and cause them to leak out of blood vessels into the damaged tissue.
The body's second line of defense against pathogens includes which response? : inflammatory