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Which effect causes winds to strike the polar front at an angle?	centrifugal effect	axial tilt	Lake Effect	coriolis effect	Mid-latitude cyclones form at the polar front. Two very different air masses blow past each other in opposite directions. The Coriolis effect causes winds to strike the polar front at an angle. Warm and cold fronts form next to each other.
Birds evolved from what type of ancestor?	fish	apes	insect	reptile	Birds evolved from a reptile ancestor, but modern birds and reptiles are very different. Birds are now the most numerous four-limbed reptiles on Earth.
Which blood cells serve to defend the body in various ways?	red blood cells	helper blood cells	blue blood cells	white blood cells	White blood cells are larger than red blood cells, but there are far fewer of them. Their role is to defend the body in various ways. For example, white blood cells called phagocytes engulf and destroy microorganisms and debris in the blood.
Eutherian mammals possess a specialized structure called the corpus callosum that links what hemispheres?	spatial	cortical	appendages	cerebral	possess a single, undivided lobe. Eutherian mammals also possess a specialized structure that links the two cerebral hemispheres, called the corpus callosum.
Which part of the brain secretes hormones that tell the pituitary gland either to secrete or to stop secreting its hormones?	thalamus	cerebrum	hippocampus	hypothalamus	The hypothalamus is actually part of the brain (see Figure below ), but it also secretes hormones . Some of its hormones “tell” the pituitary gland either to secrete or to stop secreting its hormones. In this way, the hypothalamus provides a link between the nervous and endocrine systems. The hypothalamus also produces hormones that directly regulate body processes. These hormones travel to the pituitary gland, which stores them until they are needed. The hormones include antidiuretic hormone and oxytocin.
Most reptile eggs can be laid on land, not in water and they are called what?	Transitional	aqueous	umbilical	amniotic	Most reptiles reproduce sexually and have internal fertilization. Their eggs are amniotic, so they can be laid on land instead of in water. Reptiles do not have a larval stage, and their hatchlings are relatively mature. Reptile parents provide little if any care to their young.
What do you call a small whole number placed in front of a formula in an equation in order to balance it?	function	correlation	divisible	coefficient	A coefficient is a small whole number placed in front of a formula in an equation in order to balance it. The 2 in front of the H 2 means that there are a total of atoms of hydrogen as reactants. Visually, the reaction looks like the Figure below .
Because the earth is covered with vegetation, cellulose is the most abundant of all what?	rocks	impurities	vegetables	carbohydrates	Cellulose Cellulose, a fibrous carbohydrate found in all plants, is the structural component of plant cell walls. Because the earth is covered with vegetation, cellulose is the most abundant of all carbohydrates, accounting for over 50% of all the carbon found in the vegetable kingdom. Cotton fibrils and filter paper are almost entirely cellulose (about 95%), wood is about 50% cellulose, and the dry weight of leaves is about 10%–20% cellulose. The largest use of cellulose is in the manufacture of paper and paper products. Although the use of noncellulose synthetic fibers is increasing, rayon (made from cellulose) and cotton still account for over 70% of textile production. Like amylose, cellulose is a linear polymer of glucose. It differs, however, in that the glucose units are joined by β-1,4-glycosidic linkages, producing a more extended structure than amylose (part (a) of Figure 16.11 "Cellulose"). This extreme linearity allows a great deal of hydrogen bonding between OH groups on adjacent chains, causing them to pack closely into fibers (part (b) of Figure 16.11 "Cellulose"). As a result, cellulose exhibits little interaction with water or any other solvent. Cotton and wood, for example, are completely insoluble in water and have considerable mechanical strength.
The energy of a photon is directly proportional to the frequency of the electromagnetic what?	absorption	evaporation	convection	radiation	The energy of a photon is directly proportional to the frequency of the electromagnetic radiation.
What term means the amount of space matter takes up?	mass	weight	density	volume	The amount of space matter takes up is its volume . How the volume of matter is measured depends on its state.
All of the stages that a cell goes through make up what?	photosynthesis	glycolysis	cytokineses	the cell cycle	Cell division is just one of the stages that a cell goes through during its lifetime. All of the stages that a cell goes through make up the cell cycle .
What term is used to describe birds that mate for an entire season or even stay paired for their entire life?	homogeneous	asexual	polygamous	monogamous	These birds are pairing up so that they can produce offspring. Many birds are monogamous , keeping the same mate for an entire season. In some species, they even stay paired for their entire life.
What branch of science offers an overview of the physiology of humans?	engineer	marine biology	geology	human biology	Human Biology provides an overview of the physiology of humans, from the skin inward. In addition to the skin, the skeletal, muscular, nervous, circulatory, respiratory, digestive, excretory, immune, and reproductive systems are described.
In atherosclerosis, thickening of an arterial wall due to this can restrict blood flow through the artery?	digestion	low blood pressure	high blood pressure	plaque formation
Moist skin distinguishes frogs from what animal with dry, bumpy skin?	newts	turtles	snakes	toads	Although there is actually little difference between toads and frogs, this animal would most often be called a toad. Frogs have moist skin, while toads have dry, bumpy skin.
Scientists perform experiments to test their hypotheses because sometimes the nature of natural universe is what?	this obvious	become obvious	very obvious	not obvious	Scientists perform experiments to test their hypotheses because sometimes the nature of natural universe is not obvious.
What is the term for movement toward light?	autolysis	phototropism	gravitational pull	phototaxis	Motility The majority of protists are motile, but different types of protists have evolved varied modes of movement (Figure 23.8). Some protists have one or more flagella, which they rotate or whip. Others are covered in rows or tufts of tiny cilia that they coordinately beat to swim. Still others form cytoplasmic extensions called pseudopodia anywhere on the cell, anchor the pseudopodia to a substrate, and pull themselves forward. Some protists can move toward or away from a stimulus, a movement referred to as taxis. Movement toward light, termed phototaxis, is accomplished by coupling their locomotion strategy with a light-sensing organ.
Ultraviolet radiation has the highest energy; which has the lowest?	thermal	kinetic	nuclear	infrared	Ultraviolet radiation has the highest energy; infrared the lowest.
What kind of proteins either activate or deactivate the transcription of other genes?	master complex proteins	carbon proteins	perfect regulatory proteins	master regulatory proteins	What makes the heart form during development? What makes the skin form? What makes a structure become an arm instead of a leg? These processes occur during development because of a highly specific pattern of gene expression. This intensely regulated pattern of gene expression turns genes on in the right cell at the right time, such that the resulting proteins can perform their necessary functions to ensure proper development. Transcription factors play an extremely important role during development. Many of these proteins can be considered master regulatory proteins , in the sense that they either activate or deactivate the transcription of other genes and, in turn, these secondary gene products can regulate the expression of still other genes in a regulatory cascade. Homeobox genes and gap genes are important classes of transcription factors utilized during development.
What occurs when the pancreas doesn’t make enough insulin or else the body’s cells are resistant to the effects of insulin?	colitis	hepatitis	anemia	diabetes	Diabetes is another type of noninfectious disease. Diabetes occurs when the pancreas doesn’t make enough insulin or else the body’s cells are resistant to the effects of insulin. Insulin is a hormone that helps cells absorb glucose from the blood.
According to the octet rule, magnesium is unstable because its valence shell has just two of what?	protons	quarks	neutrons	electrons	Chapter 2 1 The mass number is the total number of protons and neutrons in the nucleus of an atom. 3 The water hydrolyses, or breaks, the glycosidic bond, forming two monosaccharides. 4 D 6 A 8 B 10 C 12 B 14 A 16 C 18 A 20 B 22 D 24 B 26 A 28 B 30 D 32 B 33 These four elements—oxygen, carbon, hydrogen, and nitrogen—together make up more than 95 percent of the mass of the human body, and the body cannot make elements, so it is helpful to have them in consumables. 35 Magnesium’s 12 electrons are distributed as follows: two in the first shell, eight in the second shell, and two in its valence shell. According to the octet rule, magnesium is unstable (reactive) because its valence shell has just two electrons. It is therefore likely to participate in chemical reactions in which it donates two electrons. 37 Water is a polar molecule. It has a region of weakly positive charge and a region of weakly negative charge. These regions are attracted to ions as well as to other polar molecules. Oils are nonpolar, and are repelled by water. 39 It is not. An exchange reaction might be AB + CD → AC + BD or AB + CD → AD + BC . In all chemical reactions, including exchange reactions, the components of the reactants are identical to the components of the products. A component present among the reactants cannot disappear, nor can a component not present in the reactants suddenly appear in the products. 41 Lemon juice is one hundred times more acidic than orange juice. This means that lemon juice has a one hundred-fold greater concentration of hydrogen ions. 43 Maltose contains 12 atoms of carbon, but only 22 atoms of hydrogen and 11 atoms of oxygen, because a molecule of water is removed during its formation via dehydration synthesis.
What make distant objects appear both nearer and larger?	lasers	astrolabes	mirrors	telescopes	Telescopes make distant objects appear both nearer and larger. You can see many more stars through a telescope than with the unaided eye.
The atmosphere consists of oxygen, nitrogen, carbon dioxide, which exerts a certain pressure referred to as what?	nitrogen pressure	gravity pressure	tidal pressure	atmospheric pressure	Gas Laws and Air Composition Gas molecules exert force on the surfaces with which they are in contact; this force is called pressure. In natural systems, gases are normally present as a mixture of different types of molecules. For example, the atmosphere consists of oxygen, nitrogen, carbon dioxide, and other gaseous molecules, and this gaseous mixture exerts a certain pressure referred to as atmospheric pressure (Table 22.2). Partial pressure (Px) is the pressure of a single type of gas in a mixture of gases. For example, in the atmosphere, oxygen exerts a partial pressure, and nitrogen exerts another partial pressure, independent of the partial pressure of oxygen (Figure 22.21). Total pressure is the sum of all the partial pressures of a gaseous mixture. Dalton’s law describes the behavior of nonreactive gases in a gaseous mixture and states that a specific gas type in a mixture exerts its own pressure; thus, the total pressure exerted by a mixture of gases is the sum of the partial pressures of the gases in the mixture.
What is the oxygen-storing protein found in diving mammals' muscles called?	pheromone	pigment	hemoglobin	myoglobin
The modern atomic theory states that all matter is composed of what?	molecules	ions	quarks	atoms	The modern atomic theory states that all matter is composed of atoms.
Pressure has a significant effect on the solubility of what state of matter?	water	mixtures	solids	gases	Pressure has very little effect on the solubility of solids or liquids, but has a significant effect on the solubility of gases. Gas solubility increases as the partial pressure of a gas above the liquid increases. Suppose a certain volume of water is in a closed container with the space above it occupied by carbon dioxide gas at standard pressure. Some of the CO 2 molecules come into contact with the surface of the water and dissolve into the liquid. Now suppose that more CO 2 is added to the space above the container, causing a pressure increase. More CO 2 molecules are now in contact with the water and so more of them dissolve. Thus the solubility increases as the pressure increases. As with a solid, the CO 2 that is undissolved reaches an equilibrium with the dissolved CO 2 , represented by the following equation.
The site of some nutrient absorption, the ileum is the third part of what digestive organ?	rectum	stomach	large intestine	small intestine	The ileum is the third part of the small intestine. A few remaining nutrients are absorbed here. Like the jejunum, the inner surface of the ileum is covered with villi that increase the surface area for absorption.
If both atoms are the same, they have the same electronegativity and share what type of bond?	isotopic covalent	metabolic	ionic	nonpolar covalent
What forms when oceanic crust subducts into the mantle at convergent plate boundaries?	coral	tsunamis	glaciers	volcanic mountain ranges	Volcanic mountain ranges form when oceanic crust subducts into the mantle at convergent plate boundaries. The Andes Mountains are a chain of coastal volcanic mountains. They are forming as the Nazca plate subducts beneath the South American plate ( Figure below ).
The skin plays an important role in preventing the escape of what commonly found liquid from the body?	urine	hormones	stomach acid	water	The skin has multiple roles in the body. Many of these roles are related to homeostasis. The skin’s main functions are preventing water loss from the body and serving as a barrier to the entry of microorganisms. In addition, melanin in the skin blocks UV light and protects deeper layers from its damaging effects.
Which area of the human heart pumps the blood to the right ventricle?	left ventricle	left atrium	true atrium	right atrium	Blood from the body enters the right atrium of the heart. The right atrium pumps the blood to the right ventricle, which pumps it to the lungs.
What moves sediments after they have formed?	perspiration	photosynthesis	migration	erosion	Erosion moves sediments after they have formed. The sediments are transported away from the place where they form. There are several agents of erosion. Flowing water moves and deposits sediments. Water erodes far more material than any other erosional agent. Wind is important as an agent of erosion. This is especially true in arid climates. Ice, in glaciers, can erode enormous quantities of sediments. Gravity as a force of erosion pulls material downhill.
What involves the emission of a particle and/or energy as one atom changes into another?	enthalpy	spontaneous mutation	atomic transformation	radioactive decay	Radioactive decay involves the emission of a particle and/or energy as one atom changes into another. In most instances, the atom changes its identity to become a new element. There are four different types of emissions that occur.
Certain anaerobic parabasalid species exist in the digestive tracts of termites and wood-eating cockroaches, where they contribute an essential step in the digestion of this?	nutrients	carbonate	fiber	cellulose	Protists do not create food sources only for sea-dwelling organisms. For instance, certain anaerobic parabasalid species exist in the digestive tracts of termites and wood-eating cockroaches, where they contribute an essential step in the digestion of cellulose ingested by these insects as they bore through wood.
What do you call a group of cells of the same kind that performs the same function?	organ system	nucleus	molecule	tissue	Specialized cells may be organized into tissues. A tissue is a group of cells of the same kind that performs the same function. For example, muscle cells are organized into muscle tissue. The function of muscle tissue is to contract in order to move the body or its parts.
What is the name of a reactant in an enzymatic reaction?	tissues	membrane	Scar	substrate	Proteins Function as Enzymes If you were trying to type a paper, and every time you hit a key on your laptop there was a delay of six or seven minutes before you got a response, you would probably get a new laptop. In a similar way, without enzymes to catalyze chemical reactions, the human body would be nonfunctional. It functions only because enzymes function. Enzymatic reactions—chemical reactions catalyzed by enzymes—begin when substrates bind to the enzyme. A substrate is a reactant in an enzymatic reaction. This occurs on regions of the enzyme known as active sites (Figure 2.27). Any given enzyme catalyzes just one type of chemical reaction. This characteristic, called specificity, is due to the fact that a substrate with a particular shape and electrical charge can bind only to an active site corresponding to that substrate.
The ideal gas law is used like any other gas law, with attention paid to the unit and making sure that temperature is expressed in kelvin. however, the ideal gas law does not require a change in the conditions of a gas sample. the ideal gas law implies that if you know any three of the physical properties of a gas, you can calculate this?	unrelated	second	third	fourth	The ideal gas law is used like any other gas law, with attention paid to the unit and making sure that temperature is expressed in Kelvin. However, the ideal gas law does not require a change in the conditions of a gas sample. The ideal gas law implies that if you know any three of the physical properties of a gas, you can calculate the fourth property.
What is a reaction in which an atom or molecule is added to an unsaturated molecule, making a single product?	single reaction	complete reaction	homeostasis	an addition reaction	An addition reaction is a reaction in which an atom or molecule is added to an unsaturated molecule, making a single product . An addition reaction can be thought of as adding a molecule across the double or triple bond of an alkene or alkyne. Addition reactions are useful ways to introduce a new functional group into an organic molecule.
What is the main problem in both types of diabetes?	blood pressure	metabolism	blood concentration	insulin production	Diabetes is a disease in which insulin fails to keep blood glucose levels within a healthy range. In type 1 diabetes, the pancreas doesn’t produce insulin. In type 2 diabetes, body cells do not respond normally to insulin.
The structure of mitochondrion plays an important role in what?	magnetism	cell division	sexual reproduction	aerobic respiration	The structure of a mitochondrion is defined by an inner and outer membrane. This structure plays an important role in aerobic respiration.
Topographic maps have a horizontal scale to indicate what distances?	perpendicular	diagonal	vertical	horizontal	Topographic maps have a horizontal scale to indicate horizontal distances.
What can occur when one end of a small diameter tube is immersed in liquid?	thermal action	diffusion action	transfusion action	capillary action	Towels soak up liquids like water because the fibers of a towel are made of molecules that are attracted to water molecules. Most cloth towels are made of cotton, and paper towels are generally made from paper pulp. Both consist of long molecules of cellulose that contain many −OH groups. Water molecules are attracted to these −OH groups and form hydrogen bonds with them, which draws the H2O molecules up the cellulose molecules. The water molecules are also attracted to each other, so large amounts of water are drawn up the cellulose fibers. Capillary action can also occur when one end of a small diameter tube is immersed in a liquid, as illustrated in Figure 10.20. If the liquid molecules are strongly attracted to the tube molecules, the liquid creeps up the inside of the tube until the weight of the liquid and the adhesive forces are in balance. The smaller the diameter of the tube is, the higher the liquid climbs. It is partly by capillary action occurring in plant cells called xylem that water and dissolved nutrients are brought from the soil up through the roots and into a plant. Capillary action is the basis for thin layer chromatography, a laboratory technique commonly used to separate small quantities of mixtures. You depend on a constant supply of tears to keep your eyes lubricated and on capillary action to pump tear fluid away.
What kind of system do echinoderms possess?	photosynthetic	primitive respiratory	autonomic nerous system	water-based circulatory	15.5 Echinoderms and Chordates Echinoderms are deuterostome marine organisms. This phylum of animals bear a calcareous endoskeleton composed of ossicles covered by a spiny skin. Echinoderms possess a water-based circulatory system. The madreporite is the point of entry and exit for water for the water vascular system. The characteristic features of Chordata are a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. Chordata contains two clades of invertebrates: Urochordata (tunicates) and Cephalochordata (lancelets), together with the.
Fossils provide a window into the past. they are evidence for what?	generation	emergence	intelligent design	evolution	Fossils provide a window into the past. They are evidence for evolution.
Dominant alleles rarely cause what type of disorders, since the mutant allele is likely to die out of the population?	cancers	mutations	sex-linked disorders	genetic disorders	Few genetic disorders are controlled by dominant alleles. A mutant dominant allele is expressed in every individual who inherits even one copy of it. If it causes a serious disorder, affected people may die young and fail to reproduce. Therefore, the mutant dominant allele is likely to die out of the population.
Near-earth asteroids cross paths with earth, meaning they could collide; what are the paths called?	galaxies	trajectory	curves	orbits	Near-Earth asteroids have orbits that cross Earth’s orbit. This means that they can collide with Earth. There are over 4,500 known near-Earth asteroids. Small asteroids do sometimes collide with Earth. An asteroid about 5–10 m in diameter hits about once per year. Five hundred to a thousand of the known near-Earth asteroids are much bigger. They are over 1 kilometer in diameter. When large asteroids hit Earth in the past, many organisms died. At times, many species became extinct in a mass extinction. Astronomers keep looking for near-Earth asteroids. They hope to predict a possible collision early so they can to try to stop it.
Reflected in their relatively high level of intelligence and their ability to learn new behaviors, what organs tend to be relatively large in primates?	kidneys	lungs	hearts	brains	Primates tend to have bigger brains for their body size than other mammals. This is reflected in their relatively high level of intelligence and their ability to learn new behaviors.
This inverse relationship between solubility and temperature can be understood by looking at a what?	potassium model	nutrient model	a slide	molecular model	This inverse relationship between solubility and temperature can be understood by looking at a molecular model. Recall that higher temperatures are associated with faster particles. Gas particles are held in solution by attractive interactions with the solvent molecules. If the particles are moving slowly, these attractive forces will pull back any particles that try to escape the surface of the solution and re-enter the gas phase. However, if the gas particles are moving fast enough, these interactions will not be sufficiently strong to prevent this process from occurring. As a result, more particles are able to escape, and the amount of dissolved solute is less than it would be at a lower temperature.
Energy from sunlight enters many ecosystems through what process?	isolation	multiplication	reproduction	photosynthesis	Ecosystems need energy. Many ecosystems get their energy in the form of sunlight, which enters the ecosystem through photosynthesis . This energy then flows through the ecosystem, passed from producers to consumers . Plants are producers in many ecosystems. Energy flows from plants to the herbivores that eat the plants, and then to carnivores that eat the herbivores. The flow of energy depicts interactions of organisms within an ecosystem.
What is the world’s most serious resource problem?	deforestation	gas shortage	citrus blight	water scarcity	Most Americans have plenty of fresh, clean water. But many people around the world do not. In fact, water scarcity is the world’s most serious resource problem. How can that be? Water is almost everywhere. But much of it is unusable. What is usable is not always where it is needed.
Quarks also have a different type of charge, called what?	spontaneous charge	contrast charge	pure charge	color charge	There are six types of quarks . In ordinary matter, virtually all quarks are of the types called up and down quarks. All quarks have mass, and they have an electric charge of either +2/3 or -1/3. For example, up quarks have a charge of +2/3, and down quarks have a charge of -1/3. Quarks also have a different type of charge, called color charge, although it has nothing to do with the colors that we see. Quarks are never found alone but instead always occur in groups of two or three quarks.
Thylakoids in a chloroplast contain what plant pigment?	ultramarine	melanin	dye	chlorophyll	The structure of a chloroplast is shown in Figure below . The chloroplast is surrounded by two membranes. Inside the chloroplast are stacks of flattened sacs of membrane, called thylakoids . The thylakoids contain chlorophyll. Surrounding the thylakoids is a space called the stroma . The stroma is filled with watery ("aqueous") fluid.
The expulsion stage begins when the fetal head enters what?	uterus	head is outside vagina	you can see the umbilical cord	birth canal	Expulsion Stage The expulsion stage begins when the fetal head enters the birth canal and ends with birth of the newborn. It typically takes up to 2 hours, but it can last longer or be completed in minutes, depending in part on the orientation of the fetus. The vertex presentation known as the occiput anterior vertex is the most common presentation and is associated with the greatest ease of vaginal birth. The fetus faces the maternal spinal cord and the smallest part of the head (the posterior aspect called the occiput) exits the birth canal first. In fewer than 5 percent of births, the infant is oriented in the breech presentation, or buttocks down. In a complete breech, both legs are crossed and oriented downward. In a frank breech presentation, the legs are oriented upward. Before the 1960s, it was common for breech presentations to be delivered vaginally. Today, most breech births are accomplished by Caesarian section. Vaginal birth is associated with significant stretching of the vaginal canal, the cervix, and the perineum. Until recent decades, it was routine procedure for an obstetrician to numb the perineum and perform an episiotomy, an incision in the posterior vaginal wall and perineum. The perineum is now more commonly allowed to tear on its own during birth. Both an episiotomy and a perineal tear need to be sutured shortly after birth to ensure optimal healing. Although suturing the jagged edges of a perineal tear may be more difficult than suturing an episiotomy, tears heal more quickly, are less painful, and are associated with less damage to the muscles around the vagina and rectum. Upon birth of the newborn’s head, an obstetrician will aspirate mucus from the mouth and nose before the newborn’s first breath. Once the head is birthed, the rest of the body usually follows quickly. The umbilical cord is then double-clamped, and a cut is made between the clamps. This completes the second stage of childbirth.
What type of waste is likely to explode?	solid waste	liquid waste	mesh waste	explosive waste	Explosive waste is likely to explode. The risk of explosion may be greater if the waste is mixed with other substances.
Named after the dutch physicist, the van de graaff is a type of what device used for nuclear research?	barometer	radiation detector	electromagnetic	accelerator	Early Accelerators An early accelerator is a relatively simple, large-scale version of the electron gun. The Van de Graaff (named after the Dutch physicist), which you have likely seen in physics demonstrations, is a small version of the ones used for nuclear research since their invention for that purpose in 1932. For more, see Figure 33.7. These machines are electrostatic, creating potentials as great as 50 MV, and are used to accelerate a variety of nuclei for a range of experiments. Energies produced by Van de Graaffs are insufficient to produce new particles, but they have been instrumental in exploring several aspects of the nucleus. Another, equally famous, early accelerator is the cyclotron, invented in 1930 by the American physicist, E. Lawrence (1901–1958). For a visual representation with more detail, see Figure 33.8. Cyclotrons use fixed-frequency alternating electric fields to accelerate particles. The particles spiral outward in a magnetic field, making increasingly larger radius orbits during acceleration. This clever arrangement allows the successive addition of electric potential energy and so greater particle energies are possible than in a Van de Graaff. Lawrence was involved in many early discoveries and in the promotion of physics programs in American.
A substance that displays different colors when in the presence of an acid or a base is called what?	litmus test	pH scale	reactor	an acid-base indicator	An acid-base indicator is a substance that displays different colors when in the presence of an acid or a base. How does that work? An indicator is a weak acid that ionizes within a known pH range, usually about 2 pH units. We can represent the protonated form of the indicator molecule as HIn and the deprotonated form as In − . The following equilibrium exists for the indicator.
What is the name for the study of the plants and animals that live in fresh water bodies ?	hydrology	nematology	oceanography	limnology	Limnology is the study of the plants and animals that live in fresh water bodies. A lake has zones just like the ocean. The ecosystem of a lake is divided into three distinct zones ( Figure below ):.
What does urine leave the body through?	uterus	vagina	colon	urethra	Urine leaves the body through the urethra .
What type of plant is the dominant group of land plants?	thermal plants	grass plants	oxygen plants	vascular plants	Vascular Plants The vascular plants are the dominant and most conspicuous group of land plants. There are about 275,000 species of vascular plants, which represent more than 90 percent of Earth’s vegetation. Several evolutionary innovations explain their success and their spread to so many habitats. Vascular Tissue: Xylem and Phloem The first fossils that show the presence of vascular tissue are dated to the Silurian period, about 430 million years ago. The simplest arrangement of conductive cells shows a pattern of xylem at the center surrounded by phloem. Xylem is the tissue responsible for long-distance transport of water and minerals, the transfer of water-soluble growth factors from the organs of synthesis to the target organs, and storage of water and nutrients. A second type of vascular tissue is phloem, which transports sugars, proteins, and other solutes through the plant. Phloem cells are divided into sieve elements, or conducting cells, and supportive tissue. Together, xylem and phloem tissues form the vascular system of plants.
What term is used to describe a process in which material travels from regions of high concentration to low concentration until equilibrium is reached?	Osmosis	fission	active transport	diffusion	The folded surfaces of the gills provide a large surface area to ensure that the fish gets sufficient oxygen. Diffusion is a process in which material travels from regions of high concentration to low concentration until equilibrium is reached. In this case, blood with a low concentration of oxygen molecules circulates through the gills. The concentration of oxygen molecules in water is higher than the concentration of oxygen molecules in gills. As a result, oxygen molecules diffuse from water (high concentration) to blood (low concentration), as shown in Figure 39.5. Similarly, carbon dioxide molecules in the blood diffuse from the blood (high concentration) to water (low concentration).
Poetically speaking, nature reserves are islands of what, in a sea of habitat degraded by human activity?	ecosystem	refuge	habitats	biodiversity
Reactive elements are able to combine more what with other elements?	symmetrically	slowly	quickly	easily	Reactive elements combine easily with other elements. This explains why they usually exist in nature in compounds rather than in pure form.
What do scientists attach to aquatic animals to collect information?	fluorescent tags	ultraviolet tags	radio tags	satellite tags	Beginning in 2000, scientists from the National Oceanic and Atmospheric Administration, Stanford University, and the University of California, Santa Cruz combined to form TOPP. As part of TOPP, researchers attach satellite tags to elephant seals, white sharks, giant leatherback turtles, bluefin tuna, swordfish, and other marine animals. The tags collect information, such as how deep each animal dives, the levels of ambient light (to help determine an animal’s location), and interior and exterior body temperature. Some tags also collect information about the temperature, salinity, and depth of the water surrounding an animal to help scientists identify ocean currents. The tags send the data to a satellite, which in turn sends the data the scientists. They use this information to create maps of migration patterns and discover new information about different marine ecosystems. The information collected by TOPP offers rare insights into the lives of marine animals. Without TOPP, that information would otherwise remain unknown. With TOPP, scientists are developing a working knowledge of the particular migration routes animals take, as well as the locations of popular breeding grounds and the environmental dangers faced by different species. TOPP has shed light on how we can better protect the leatherback turtle and other endangered species.
Upon ovulation, the oocyte released by the ovary is swept into where?	umbilical cord	placental barrier	vas deferens	uterine tube	Contact Between Sperm and Oocyte Upon ovulation, the oocyte released by the ovary is swept into—and along—the uterine tube. Fertilization must occur in the distal uterine tube because an unfertilized oocyte cannot survive the 72-hour journey to the uterus. As you will recall from your study of the oogenesis, this oocyte (specifically a secondary oocyte) is surrounded by two protective layers. The corona radiata is an outer layer of follicular (granulosa) cells that form around a developing oocyte in the ovary and remain with it upon ovulation. The underlying zona pellucida (pellucid = “transparent”) is a transparent, but thick, glycoprotein membrane that surrounds the cell’s plasma membrane. As it is swept along the distal uterine tube, the oocyte encounters the surviving capacitated sperm, which stream toward it in response to chemical attractants released by the cells of the corona radiata. To reach the oocyte itself, the sperm must penetrate the two protective layers. The sperm first burrow through the cells of the corona radiata. Then, upon contact with the zona pellucida, the sperm bind to receptors in the zona pellucida. This initiates a process called the acrosomal reaction in which the enzyme-filled “cap” of the sperm, called the acrosome, releases its stored digestive enzymes. These enzymes clear a path through the zona pellucida that allows sperm to reach the oocyte. Finally, a single sperm makes contact with sperm-binding receptors on the oocyte’s plasma membrane (Figure 28.2). The plasma membrane of that sperm then fuses with the oocyte’s plasma membrane, and the head and mid-piece of the “winning” sperm enter the oocyte interior. How do sperm penetrate the corona radiata? Some sperm undergo a spontaneous acrosomal reaction, which is an acrosomal reaction not triggered by contact with the zona pellucida. The digestive enzymes released by this reaction digest the extracellular matrix of the corona radiata. As you can see, the first sperm to reach the oocyte is never the one to fertilize it. Rather, hundreds of sperm cells must undergo the acrosomal reaction, each helping to degrade the corona radiata and.
Giardiasis and malaria are diseases caused by what organism?	bacteria	worms	larvae	protozoa	Many human diseases are caused by protists. Most of them are caused by protozoa. They are parasites that invade and live in the human body. The parasites get a place to live and nutrients from the human host. In return, they make the host sick. Examples of human diseases caused by protozoa include giardiasis and malaria.
The number of waves that pass a fixed point in a given amount of time is referred to as what?	wave harmonics	tendency frequency	wave speed	wave frequency	Wave frequency is the number of waves that pass a fixed point in a given amount of time.
The name carbon tetrachloride implies one carbon atom and four of which other atoms?	iodine	calcium	nitrogen	chlorine	The name carbon tetrachloride implies one carbon atom and four chlorine atoms, so the formula is CCl4. Saylor URL: http://www. saylor. org/books.
Most of a mushroom's surface area is actually where?	air	hidden	underwater	underground	Fungi can grow fast because they are such good eaters. Fungi have lots of surface area, and this large surface area “eats” or absorbs. Surface area is how much exposed area an organism has, compared to their overall volume. Most of a mushroom's surface area is actually underground. If you see a mushroom in your yard, that is just a small part of a larger fungus growing underground.
Interneurons carry what back and forth between sensory and motor neurons?	flux impulses	sciatica	electricity	nerve impulses	Interneurons carry nerve impulses back and forth between sensory and motor neurons.
What are the mineral deposits that fill in underground cracks called?	motherlode	cores	currents	veins	Underground water can be heated by magma. The hot water moves through cracks below Earth’s surface. Hot water can hold more dissolved particles than cold water. The hot, salty solution has chemical reactions with the rocks around it. The water picks up more dissolved particles. As it flows through open spaces in rocks, the water deposits solid minerals. When a mineral fills cracks in rocks, the deposits are called “veins. ” Figure below shows a white quartz vein. When the minerals are deposited in open spaces, large crystals grow. These rocks are called geodes. Figure below shows a “geode” that was formed when amethyst crystals grew in an open space in a rock.
Some of the small moons of saturn are found within what features distinctive to the planet?	craters of saturn	interior of saturn	crest of saturn	rings of saturn	As of 2011, over 60 moons have been identified around Saturn. Only seven of Saturn’s moons are round. All but one is smaller than Earth’s Moon. Some of the very small moons are found within the rings. All the particles in the rings are like little moons, because they orbit around Saturn. Someone must decide which ones are large enough to call moons.
An image that is double the size of the object would have what?	illumination	stimulation	configuration	magnification	The size of an object’s image is larger (or smaller) than the object itself by its magnification, . The level of magnification is proportional to the ratio of and . An image that is double the size of the object would have magnification .
What is made up of bands of cells that contract for movement?	cartilage	vascular tissue	collagen	muscle tissue	Muscle tissue is made up of bands of cells that contract and allow movement.
What is the name of the muscular tube that carries urine out of the body?	bladder	rectum	uterus	urethra	From the collecting ducts of the kidneys, urine enters the ureters , two muscular tubes that move the urine by peristalsis to the bladder (see Figure above ). The bladder is a hollow, sac-like organ that stores urine. When the bladder is about half full, it sends a nerve impulse to a sphincter to relax and let urine flow out of the bladder and into the urethra. The urethra is a muscular tube that carries urine out of the body. Urine leaves the body through another sphincter in the process of urination . This sphincter and the process of urination are normally under conscious control.
Tissues are organized by what?	structures	branches	lipids	cells	Cells are organized into tissues, and tissues form organs.
Carbon released by burning fossil fuels contributes to what effect in the atmosphere?	cloud effect	shielding effect	smog effect	greenhouse effect	Burning of fossil fuels, such as oil, releases carbon into the atmosphere. This carbon must be cycled - removed from the atmosphere - back into living organisms, or it stays in the atmosphere. Increased carbon in the atmosphere contributes to the greenhouse effect on Earth.
What are a class of biochemical compounds that living things use to store energy?	calories	hydrocarbons	proteins	lipids	Lipids are a class of biochemical compounds that living things use to store energy. Types of lipids include fats and oils.
Which element has an atomic number of 16?	oxygen	acid	methane	sulfur	The atomic number of sulfur is 16. Therefore, in a neutral atom of sulfur, there are 16 electrons. Saylor URL: http://www. saylor. org/books.
Fossil evidence indicates that the ancestors of humans originated on which continent?	south america	north america	australia	africa
What will spores that eventually germinate develop into?	hydra	yeast cells	gametes	new hyphae	This phylogenetic tree is based on comparisons of ribosomal RNA base sequences among living organisms. The tree divides all organisms into three domains: Bacteria, Archaea, and Eukarya. Humans and other animals belong to the Eukarya domain. From this tree, organisms that make up the domain Eukarya appear to have shared a more recent common ancestor with Archaea than Bacteria.
A binary molecular compound is made up of two of what?	wafers	compounds	cells	elements	A binary molecular compound is a molecular compound that is composed of two elements. The elements that combine to form binary molecular compounds are both nonmetal atoms. This contrasts with ionic compounds, which were formed from a metal ion and a nonmetal ion. Therefore, binary molecular compounds are different because ionic charges cannot be used to name them or to write their formulas. Another difference is that two nonmetal atoms will frequently combine with one another in a variety of ratios. Consider the elements nitrogen and oxygen. They combine to make several compounds including NO, NO 2 , and N 2 O. They all can’t be called nitrogen oxide. How would someone know which one you were talking about? Each of the three compounds has very different properties and reactivity. A system to distinguish between compounds such as these is necessary.
Sound, like all waves, travels at a certain speed and has the properties of frequency and this?	energy	gravity	momentum	wavelength	Sound, like all waves, travels at a certain speed and has the properties of frequency and wavelength. You can observe direct evidence of the speed of sound while watching a fireworks display. The flash of an explosion is seen well before its sound is heard, implying both that sound travels at a finite speed and that it is much slower than light. You can also directly sense the frequency of a sound. Perception of frequency is called pitch. The wavelength of sound is not directly sensed, but indirect evidence is found in the correlation of the size of musical instruments with their pitch. Small instruments, such as a piccolo, typically make high-pitch sounds, while large instruments, such as a tuba, typically make low-pitch sounds. High pitch means small wavelength, and the size of a musical instrument is directly related to the wavelengths of sound it produces. So a small instrument creates short-wavelength sounds. Similar arguments hold that a large instrument creates long-wavelength sounds. The relationship of the speed of sound, its frequency, and wavelength is the same as for all waves:.
Do bacteria sexually reproduce?	they don't reproduce	sometimes	yes	no	Are there male and female bacteria? Of course the answer is no. So, sexual reproduction does not occur in bacteria. But not all new bacteria are clones. This is because bacteria can acquire new DNA. This process occurs in three different ways:.
What is type of sugar is produced through photosynthesis?	glutamate	carbohydrates	insulin	glucose	The energy of the sun is first captured by producers ( Figure below ), organisms that can make their own food. Many producers make their own food through the process of photosynthesis . The "food" the producers make is the sugar, glucose . Producers make food for the rest of the ecosystem. As energy is not recycled, energy must consistently be captured by producers. This energy is then passed on to the organisms that eat the producers, and then to the organisms that eat those organisms, and so on.
The light-sensing cells in the retina are called rods and what else?	light cells	sensor cells	stents	cones	The back of the eye is covered by a thin layer called the retina. This is where the image of the object normally forms. The retina consists of special light-sensing cells called rods and cones. Rods sense dim light. Cones sense different colors of light.
Lampreys possess a large round sucker, lined with teeth, that surrounds the mouth and is used to feed on what?	marrow	parasites	herbivores	blood	Like hagfish, lampreys also lack scales, but they have fins and a partial backbone. The most striking feature of lampreys is a large round sucker, lined with teeth, that surrounds the mouth (see Figure below ). Lampreys use their sucker to feed on the blood of other fish species.
What is the type of plant that has a single cotelydon in the seedling?	moss	dicot	conifer	monocot	Monocots Plants in the monocot group are primarily identified as such by the presence of a single cotyledon in the seedling. Other anatomical features shared by monocots include veins that run parallel to the length of the leaves, and flower parts that are arranged in a three- or six-fold symmetry. True woody tissue is rarely found in monocots. In palm trees, vascular and parenchyma tissues produced by the primary and secondary thickening meristems form the trunk. The pollen from the first angiosperms was monosulcate, containing a single furrow or pore through the outer layer. This feature is still seen in the modern monocots. Vascular tissue of the stem is not arranged in any particular pattern. The root system is mostly adventitious and unusually positioned, with no major tap root. The monocots include familiar plants such as the true lilies (which are at the origin of their alternate name of Liliopsida), orchids, grasses, and palms. Many important crops are monocots, such as rice and other cereals, corn, sugar cane, and tropical fruits like bananas and pineapples (Figure 26.17).
What element is essential for amino acid and nucleic acid production?	hydrogen	oxygen	carbon	nitrogen
In plants and algae where does photosynthesis takes place in?	cytoplasm	cell wall	nucleus	chloroplasts	In plants and algae, photosynthesis takes place in chloroplasts. (Photosynthetic bacteria have other structures for this purpose. ) A chloroplast is a type of plastid, or plant organelle. It contains the green pigment known as chlorophyll . The presence of chloroplasts in plant cells is one of the major ways they differ from animal cells. You can see chloroplasts in plant cells Figure below .
What is crucial for the fermentation progress in making bread?	cold	larvae	fruit	yeast	Yeasts are crucial for the fermentation process that makes beer, wine, and bread. Fermentation occurs in the absence of oxygen and allows the first step of cellular respiration, glycolysis, to continue.
What hormone does the endocrine system secrete to help cells absorb blood sugar?	Cortisol	glucose	testosterone	insulin	After you eat and digest a sugary snack, the level of sugar in your blood quickly rises. In response, the endocrine system secretes the hormone insulin. Insulin helps cells absorb sugar from the blood. This causes the level of sugar in the blood to fall back to its normal level.
What part of the sporophyte produces microspores that form male gametophytes and megaspores that form female gametophytes?	leaves	chloroplasts	pollen	flower
This calcification prevents diffusion of nutrients into the matrix, resulting in what dying and the opening up of cavities in the diaphysis cartilage?	keratinocytes	nanoparticles	phytocytes	chondrocytes	matrix and deposit calcium, which hardens the matrix. The non-mineralized portion of the bone or osteoid continues to form around blood vessels, forming spongy bone. Connective tissue in the matrix differentiates into red bone marrow in the fetus. The spongy bone is remodeled into a thin layer of compact bone on the surface of the spongy bone. Endochondral Ossification Endochondral ossification is the process of bone development from hyaline cartilage. All of the bones of the body, except for the flat bones of the skull, mandible, and clavicles, are formed through endochondral ossification. In long bones, chondrocytes form a template of the hyaline cartilage diaphysis. Responding to complex developmental signals, the matrix begins to calcify. This calcification prevents diffusion of nutrients into the matrix, resulting in chondrocytes dying and the opening up of cavities in the diaphysis cartilage. Blood vessels invade the cavities, and osteoblasts and osteoclasts modify the calcified cartilage matrix into spongy bone. Osteoclasts then break down some of the spongy bone to create a marrow, or medullary, cavity in the center of the diaphysis. Dense, irregular connective tissue forms a sheath (periosteum) around the bones. The periosteum assists in attaching the bone to surrounding tissues, tendons, and ligaments. The bone continues to grow and elongate as the cartilage cells at the epiphyses divide. In the last stage of prenatal bone development, the centers of the epiphyses begin to calcify. Secondary ossification centers form in the epiphyses as blood vessels and osteoblasts enter these areas and convert hyaline cartilage into spongy bone. Until adolescence, hyaline cartilage persists at the epiphyseal plate (growth plate), which is the region between the diaphysis and epiphysis that is responsible for the lengthwise growth of long bones (Figure 38.21).
What is the greek word meaning "to help make things easier"?	mode	toy	battery	machine	9.5 Simple Machines Simple machines are devices that can be used to multiply or augment a force that we apply – often at the expense of a distance through which we apply the force. The word for “machine” comes from the Greek word meaning “to help make things easier. ” Levers, gears, pulleys, wedges, and screws are some examples of machines. Energy is still conserved for these devices because a machine cannot do more work than the energy put into it. However, machines can reduce the input force that is needed to perform the job. The ratio of output to input force magnitudes for any simple machine is called its mechanical advantage (MA).
High levels of radiation can remove electrons from?	humans	water	acids	metals	Nonliving things can also be damaged by radiation. For example, high levels of radiation can remove electrons from metals. This may weaken metals in nuclear power plants and space vehicles, both of which are exposed to very high levels of radiation.
What is the only planet we know that has plate techtonics?	Jupiter	Saturn	Mars	earth	The Earth is divided into many plates. These plates move around on the surface. The plates collide or slide past each other. One may even plunge beneath another. Plate motions cause most geological activity. This activity includes earthquakes, volcanoes, and the buildup of mountains. The reason for plate movement is convection in the mantle. Earth is the only planet that we know has plate tectonics.
Variation in muscle cells gives further insight into some benefits of what type of respiration?	aerobic	natural	enzymatic	anaerobic	Variation in muscle cells gives further insight into some benefits of anaerobic respiration. In vertebrate muscles, lactic acid fermentation allows muscles to produce ATP quickly during short bursts of strenuous activity. Muscle cells specialized for this type of activity show differences in structure as well as chemistry. Red muscle fibers are “dark” because they have a rich blood supply for a steady supply of oxygen, and a protein, myoglobin, which holds extra oxygen. They also contain more mitochondria, the organelle in which the Krebs cycle and electron transport chain conclude aerobic respiration. This is endurance muscle. White muscle cells are “light” because they lack the rich blood supply, have fewer mitochondria, and store the carbohydrate glycogen rather than oxygen. This is muscle built for sprinting.
Violet and red are two types of what kind of light?	radioactive	infrared	ultraviolet	visible	Figure 8.12 The colors of visible light do not carry the same amount of energy. Violet has the shortest wavelength and therefore carries the most energy, whereas red has the longest wavelength and carries the least amount of energy. (credit: modification of work by NASA).
The duodenum is a part of which part of the gi tract?	ulna	large intense	pharynx	small intestine	The duodenum is the first and shortest part of the small intestine. Most chemical digestion takes place here, and many digestive enzymes are active in the duodenum (see Table below ). Some are produced by the duodenum itself. Others are produced by the pancreas and secreted into the duodenum.
A complete ionic equation is a chemical equation in which the dissolved ionic compounds are written as what?	realized ions	charged ions	joined ions	separated ions	When chemicals in solution react, the proper way of writing the chemical formulas of the dissolved ionic compounds is in terms of the dissociated ions, not the complete ionic formula. A complete ionic equation is a chemical equation in which the dissolved ionic compounds are written as separated ions. Solubility rules are very useful in determining which ionic compounds are dissolved and which are not. For example, when NaCl(aq) reacts with AgNO3(aq) in a double-replacement reaction to precipitate AgCl(s) and form NaNO3(aq), the complete ionic equation includes NaCl, AgNO3, and NaNO3 written as separated ions:.

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