allenai/sciq · Datasets at Hugging Face

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Deficiency of what is symptomized by nausea, fatigue and dizziness, and can be triggered by excessive sweating?	calories	impurities	salts	electrolytes	An alkaline battery is a variation on the zinc-carbon dry cell. The alkaline battery has no carbon rod and uses a paste of zinc metal and potassium hydroxide instead of a solid metal anode. The cathode half-reaction is the same, but the anode half-reaction is different.
Most thoracic vertebrae have two facets that articulate with the head of what structure?	pelvic	calf	heart	rib	Thoracic Vertebrae The bodies of the thoracic vertebrae are larger than those of cervical vertebrae (Figure 7.26). The characteristic feature for a typical midthoracic vertebra is the spinous process, which is long and has a pronounced downward angle that causes it to overlap the next inferior vertebra. The superior articular processes of thoracic vertebrae face anteriorly and the inferior processes face posteriorly. These orientations are important determinants for the type and range of movements available to the thoracic region of the vertebral column. Thoracic vertebrae have several additional articulation sites, each of which is called a facet, where a rib is attached. Most thoracic vertebrae have two facets located on the lateral sides of the body, each of which is called a costal facet (costal = “rib”). These are for articulation with the head (end) of a rib. An additional facet is located on the transverse process for articulation with the tubercle of a rib.
Thrombocytes are more commonly known by what name?	droplets	chromosomes	molecules	platelets	Platelets and Coagulation Factors Blood must clot to heal wounds and prevent excess blood loss. Small cell fragments called platelets (thrombocytes) are attracted to the wound site where they adhere by extending many projections and releasing their contents. These contents activate other platelets and also interact with other coagulation factors, which convert fibrinogen, a water-soluble protein present in blood serum into fibrin (a non-water soluble protein), causing the blood to clot. Many of the clotting factors require vitamin K to work, and vitamin K deficiency can lead to problems with blood clotting. Many platelets converge and stick together at the wound site forming a platelet plug (also called a fibrin clot), as illustrated in Figure 40.8b. The plug or clot lasts for a number of days and stops the loss of blood. Platelets are formed from the disintegration of larger cells called megakaryocytes, like that shown in Figure 40.8a. For each megakaryocyte, 2000–3000 platelets are formed with 150,000 to 400,000 platelets present in each cubic millimeter of blood. Each platelet is disc shaped and 2–4 μm in diameter. They contain many small vesicles but do not contain a nucleus.
What is the term for the remains or traces of living organisms?	deposits	remains	ethings	fossils	Fossils are the remains or traces of living organisms.
What type of disease is caused by pathogens?	autoimmune diseases	viral diseases	nervous diseases	infectious diseases	Infectious diseases are diseases that are caused by pathogens. Human pathogens include bacteria, viruses, fungi, and protozoa. Different pathogens spread in different ways. Pathogens may spread through contaminated food or water, sexual contact, droplets in the air from coughs or sneezes, contaminated objects or surfaces, or vectors.
Worms grow to adult size without going through what stage?	growth	egg	development	larval	In some species, the same individual produces both sperm and eggs. But worms mate to exchange sperm, rather than self-fertilizing their own eggs. Fertilized eggs are deposited in a mucous cocoon. Offspring emerge from the cocoon looking like small adults. They grow to adult size without going through a larval stage.
What serves as a first responder to pathogenic threats that bypass natural physical and chemical barriers of the body?	immense immune system	cells immune system	super immune system	innate immune system	CHAPTER SUMMARY 42.1 Innate Immune Response The innate immune system serves as a first responder to pathogenic threats that bypass natural physical and chemical barriers of the body. Using a combination of cellular and molecular attacks, the innate immune system identifies the nature of a pathogen and responds with inflammation, phagocytosis, cytokine release, destruction by NK cells, and/or a complement system. When innate mechanisms are insufficient to clear an infection, the adaptive immune response is informed and mobilized.
Of the three basic types of emissions, which has the highest penetrating power?	chemical radiation	ultraviolet radiation	fluid radiation	gamma radiation	Of the three basic types of emissions, gamma radiation has the highest penetrating power. Thick, high density materials (such as lead) are required to stop gamma emissions. The thickness of the shielding will determine the effectiveness of the protection offered by the lead.
True animals are divided into those with radial versus bilateral styles of what?	magnetic	attracted	molecular	symmetry	27.2 Features Used to Classify Animals Organisms in the animal kingdom are classified based on their body morphology and development. True animals are divided into those with radial versus bilateral symmetry. Generally, the simpler and often non-motile animals display radial symmetry. Animals with radial symmetry are also generally characterized by the development of two embryological germ layers, the endoderm and ectoderm, whereas animals with bilateral symmetry are generally characterized by the development of a third embryological germ layer, the mesoderm. Animals with three germ layers, called triploblasts, are further characterized by the presence or absence of an internal body cavity called a coelom. The presence of a coelom affords many advantages, and animals with a coelom may be termed true coelomates or pseudocoelomates, depending on which tissue gives rise to the coelom. Coelomates are further divided into one of two groups called protostomes and deuterostomes, based on a number of developmental characteristics, including differences in zygote cleavage and method of coelom formation.
While still an early fetus, what is the skeleton made of?	gel	ligament	membrane	cartilage	Early in the development of a human fetus, the skeleton is made entirely of cartilage. The relatively soft cartilage gradually turns into hard bone through ossification . This is a process in which mineral deposits replace cartilage. As shown in Figure below , ossification of long bones, which are found in the arms and legs, begins at the center of the bones and continues toward the ends. By birth, several areas of cartilage remain in the skeleton, including the ends of the long bones. This cartilage grows as the long bones grow, so the bones can keep increasing in length during childhood.
What forms the pathway of water and nutrients from roots to leaves and flower?	the pistil	the stamen	the stigma	the stem
What proteins span the entire plasma membrane?	cytoplasm	sequence	amino acids	transmembrane	Transmembrane proteins span the entire plasma membrane. Their function is mainly to regulate the transport of specific molecules across the membrane. There are two basic types of transmembrane proteins, alpha-helical and beta-barrels, which are discussed in Organic Compounds: Proteins (Advanced) .
Why is blue cheese blue?	fermentation	artificial dye	bacteria	fungus	Stuart Webster. Blue cheese is blue because of the fungus growing throughout it. . CC BY 2.0.
What type of joint are ball-and-socket, hinge, and pivot examples of?	fixed	retractable	artificial	movable	Joints may be immovable, partly movable, or movable. Types of movable joints include ball-and-socket, hinge, and pivot joints.
Are valence electrons attracted more or less strongly when they are farther from the nucleus?	differently	equally	more strongly	less strongly	The reactivity of alkaline Earth metals increases from the top to the bottom of the group. That’s because the atoms get bigger from the top to the bottom, so the valence electrons are farther from the nucleus. When valence electrons are farther from the nucleus, they are attracted less strongly by the nucleus and more easily removed from the atom. This makes the atom more reactive.
What do we call the predictable distribution of molecular speeds found in gas of many molecules?	kemp - boltzmann distribution	mitchell - boltzmann distribution	burns - boltzmann distribution	maxwell-boltzmann distribution	• The motion of individual molecules in a gas is random in magnitude and direction. However, a gas of many molecules has a predictable distribution of molecular speeds, known as the Maxwell-Boltzmann distribution.
Name the simple sugar that is a component of starch.	insulin	Fructose	Splenda	glucose	3.2 \| Carbohydrates By the end of this section, you will be able to: • Discuss the role of carbohydrates in cells and in the extracellular materials of animals and plants • Explain the classifications of carbohydrates • List common monosaccharides, disaccharides, and polysaccharides Most people are familiar with carbohydrates, one type of macromolecule, especially when it comes to what we eat. To lose weight, some individuals adhere to “low-carb” diets. Athletes, in contrast, often “carb-load” before important competitions to ensure that they have enough energy to compete at a high level. Carbohydrates are, in fact, an essential part of our diet; grains, fruits, and vegetables are all natural sources of carbohydrates. Carbohydrates provide energy to the body, particularly through glucose, a simple sugar that is a component of starch and an ingredient in many staple foods. Carbohydrates also have other important functions in humans, animals, and plants.
What do vertebrates have which invertebrates do not?	tails	appendages	fangs	backbones	Vertebrates have a backbone, but invertebrates do not. Except for the chordates, all animal phyla consist only of invertebrates. Chordates include both vertebrates and invertebrates.
Occuring throughout the lifespan of the organism, what stages proceed in a certain order?	genetic stages	yearly stages	life effectiveness stages	life cycle stages
The fetus is connected to what by a tube called the umbilical cord?	Fallopian tube	Stomach	Intestines	placenta	The placenta is a spongy mass of blood vessels. Some of the vessels come from the mother. Some come from the fetus. The placenta is attached to the inside of the mother’s uterus. The fetus is connected to the placenta by a tube called the umbilical cord . The cord contains two arteries and a vein. Substances pass back and forth between the mother’s and fetus’s blood through the placenta and cord. Oxygen and nutrients pass from the mother to the fetus. Carbon dioxide passes from the fetus to the mother.
What are most fresh fruits, vegetables, whole grains rich in?	magnesium	calcium	cholesterol	cellulose
What term tells you how quickly the angle changes and can occur in either clockwise or counterclockwise directions?	turning velocity	emit velocity	shift velocity	angular velocity	The angular velocity tells you how quickly the angle changes. In more formal language, the rate of change of , the angular position, is called the angular velocity . The direction of angular velocity is either clockwise or counterclockwise. Analogously, the rate of change of is the angular acceleration .
What term is used to describe how fast a chemical reaction occurs?	velocity	response time	catalysis	reaction rate	How fast a chemical reaction occurs is called the reaction rate . Several factors affect the rate of a given chemical reaction. They include the:.
What is the term for protists that produce spores, such as the toxoplasm?	newborns	protozoans	spermatozoa	sporozoans	The sporozoans are protists that produce spores, such as the toxoplasma . These protists do not move at all. The spores develop into new protists.
Why does neptune's appearance change?	the speed of rotation	the seasons	the changing orbit	turbulent atmosphere	Neptune's appearance changes due to its turbulent atmosphere. Winds are stronger than on any other planet in the solar system. Wind speeds can reach 1,100 km/h (700 mph). This is close to the speed of sound! The rapid winds surprised astronomers. This is because Neptune receives little energy from the Sun to power weather systems. It is not surprising that Neptune is one of the coldest places in the solar system. Temperatures at the top of the clouds are about –218°C (–360°F).
Changing levels of what substances partly explain emotional ups and downs in teens?	enzymes	nutrients	acids	hormones	Many teens have emotional ups and downs. This is at least partly due to their changing hormone levels.
What term refers to larger evolutionary changes that result in new species?	substantial evolution	Microevolution	Potential evolution	macroevolution	Macroevolution refers to larger evolutionary changes that result in new species.
What do you call a lens that causes the light rays to bend away from its axis?	converging lens	optical lens	axilens	diverging lens	• A lens that causes the light rays to bend away from its axis is called a diverging lens. • Ray tracing is the technique of graphically determining the paths that light rays take. • The image in which light rays from one point on the object actually cross at the location of the image and can be projected onto a screen, a piece of film, or the retina of an eye is called a real image. • Thin lens equations are.
Diffusion can occur across a semipermeable membrane, such as the cell membrane, as long as a what exists?	differential	polarity	parity	concentration gradient	Diffusion can occur across a semipermeable membrane, such as the cell membrane, as long as a concentration gradient exists. Molecules will continue to flow in this manner until equilibrium is reached. At equilibrium, there is no longer an area of high concentration or low concentration, and molecules flow equally in both directions across the semipermeable membrane. At equilibrium, equal amounts of a molecule are entering and leaving a cell.
Scientists use what scale to illustrate the order in which events on earth have happened?	cataclysmic time scale	ecological succession	fossil record	geologic time scale	Scientists use the geologic time scale to illustrate the order in which events on Earth have happened.
What will happen if the gas particles inside an inflated balloon suddenly stop moving?	balloon inflates	balloon falls	balloon bursts	balloon deflates	Gas molecules also exert pressure. Earth’s atmosphere exerts pressure because gravity acts on the huge number of gas particles contained in the atmosphere, holding it in place. Pressure is also exerted by a small sample of gas, such as that which is contained in a balloon. Gas pressure is the pressure that results from collisions of gas particles with an object. Inside the balloon, the gas particles collide with the balloon’s inner walls. It is those collisions which keep the balloon inflated. If the gas particles were to suddenly stop moving, the balloon would instantly deflate. The Figure below is an illustration of gas particles exerting pressure inside a container.
What are the major sites of gibberellin production?	stem and roots	flower and fruit	soil and leaves	young roots and leaves
What is required for interconversion between the two forms of an isomeric pair?	turn and reforming	couple and reforming	fixing and reforming	breaking and reforming	Stereoisomers Molecules with the same connectivity but different arrangements of the atoms in space are called stereoisomers. There are two types of stereoisomers: geometric and optical. Geometric isomers differ in the relative position(s) of substituents in a rigid molecule. (For more information on stereoisomers, see Chapter 23 "The ", Section 23.4 "Coordination Compounds". ) Simple rotation about a C–C σ bond in an alkene, for example, cannot occur because of the presence of the π bond. The substituents are therefore rigidly locked into a particular spatial arrangement (part (a) in Figure 2.16 "Some Simple (a) Alkenes, (b) Alkynes, and (c) Cyclic Hydrocarbons"). Thus a carbon–carbon multiple bond, or in some cases a ring, prevents one geometric isomer from being readily converted to the other. The members of an isomeric pair are identified as either cis or trans, and interconversion between the two forms requires breaking and reforming one or more bonds. Because their structural difference causes them to have different physical and chemical properties, cis and trans isomers are actually two distinct chemical compounds.
Bacteria reproduce through what process, where the chromosome copies itself, forming two genetically identical copies?	nuclear fission	multiple fission	residual fission	binary fission	Bacteria reproduce through a process called binary fission . During binary fission, the chromosome copies itself, forming two genetically identical copies. Then, the cell enlarges and divides into two new daughter cells. The two daughter cells are identical to the parent cell. Binary fission can happen very rapidly. Some species of bacteria can double their population in less than ten minutes!.
Water molecules are polar, so they form what type of bonds?	helium	carbon	oxygen	hydrogen	Water molecules are polar, so they form hydrogen bonds. This gives water unique properties, such as a relatively high boiling point, high specific heat, cohesion, adhesion and density.
The cecum is the first part of what structure, where wastes in a liquid state enter from the small intestine?	appendix	duodenum	esophagus	large intestine	http://www. explainthatstuff. com/how-geiger-counters-work. html.
What are the "levels" in a food chain or web called?	gauges	parts	root	trophic	Energy is passed up a food chain or web from lower to higher trophic levels. However, generally only about 10 percent of the energy at one level is available to the next level. This is represented by the ecological pyramid in Figure below . What happens to the other 90 percent of energy? It is used for metabolic processes or given off to the environment as heat. This loss of energy explains why there are rarely more than four trophic levels in a food chain or web. Sometimes there may be a fifth trophic level, but usually there’s not enough energy left to support any additional levels.
Are bones considered living or dead tissues?	dead	decaying	decomposing	living	From seeing a skeleton, you might think that bones are just dead, hollow structures. But in a living person, those hollow spaces are full of living cells. Bones have a blood supply and nerves. Bones are a living tissue.
What forms when water in the atmosphere condenses on dust particles suspended in the air?	wind	hail	snow	clouds
What are the two types of fermentation?	lactic acid and fermaldehyde	acetic and anhydrous	alcoholic and alchemical	lactic acid and alcoholic	There are two types of fermentation: lactic acid fermentation and alcoholic fermentation. Both types of fermentation are described below. You can also watch animations of both types at this link: http://www. cst. cmich. edu/users/schul1te/animations/fermentation. swf .
Aging occurs as cells lose their ability to do what?	join	grow	build	divide	During early adulthood, people form intimate relationships and start careers. Serious health problems start showing up in middle adulthood and old age. Aging occurs as cells lose their ability to divide.
What is it called when liquid water falls from the sky?	erosion	sedimentation	water cycling	precipitation
Applying a pressure greater than the osmotic pressure of a solution will do what?	normal osmosis	ultrafiltration	osmosis	reverse osmosis	Figure 11.26 Applying a pressure greater than the osmotic pressure of a solution will reverse osmosis. Solvent molecules from the solution are pushed into the pure solvent.
The molecule pictured above is thyroxine, a compound produced by which gland?	gallbladder	stomach	kidney	thyroid	The molecule pictured above is thyroxine, a compound produced by the thyroid gland. This molecule regulates how the body uses energy. In a condition known as hypothyroidism, the thyroid makes less thyroxine than normal. A person with this disease feels tired all the time and often puts on weight. Treatment with thyroid hormone supplements takes care of the problem.
Birds generally practice what kind of relationship, with both parents helping to care for the young?	homologous	carnivorous	synonomous	monogamous	Birds generally are monogamous, and both parents help to care for the young.
Gravitropism ensures that roots grow into the soil and that shoots grow toward what?	the south pole	the north pole	trees	sunlight	Plant Responses to Gravity Whether or not they germinate in the light or in total darkness, shoots usually sprout up from the ground, and roots grow downward into the ground. A plant laid on its side in the dark will send shoots upward when given enough time. Gravitropism ensures that roots grow into the soil and that shoots grow toward sunlight. Growth of the shoot apical tip upward is called negative gravitropism, whereas growth of the roots downward is called positive gravitropism. Amyloplasts (also known as statoliths) are specialized plastids that contain starch granules and settle downward in response to gravity. Amyloplasts are found in shoots and in specialized cells of the root cap. When a plant is tilted, the statoliths drop to the new bottom cell wall. A few hours later, the shoot or root will show growth in the new vertical direction. The mechanism that mediates gravitropism is reasonably well understood. When amyloplasts settle to the bottom of the gravity-sensing cells in the root or shoot, they physically contact the endoplasmic reticulum (ER), causing the release of calcium ions from inside the ER. This calcium signaling in the cells causes polar transport of the plant hormone IAA to.
What is the mass of one mole of any given substance?	solute mass	atomic mass	protons mass	molar mass	Molar mass is the mass of one mole of any given substance.
The corona surrounds which major object in our solar system?	Jupiter	Neptune	Earth's moon	the sun	The corona is the halo around the Sun.
Respiration that occurs in the cells is called?	biological respiration	electromagnetic respiration	plasma respiration	cellular respiration	Another kind of respiration takes place within body cells. This kind of respiration is called cellular respiration. It’s the process in which cells obtain energy by “burning” glucose. Both types of respiration are connected. Cellular respiration uses oxygen and produces carbon dioxide. Respiration by the respiratory system supplies the oxygen needed for cellular respiration. It also removes the carbon dioxide produced by cellular respiration.
Metabolism is an emergent property of life that arises from orderly interactions between what?	nutrients	tissues	body systems	molecules
During cellular respiration, carbons from the glucose molecule are changed back into what gas?	liquid dioxide	deformation dioxide	carbon monoxide	carbon dioxide	In biological systems, matter is continuously changing states as well. For example, carbon in the form of the gas carbon dioxide is changed into glucose, a solid. This change, of course, occurs during photosynthesis. During cellular respiration, carbons from the glucose molecule are changed back into the carbon dioxide gas.
How does the distance between galaxies change as the universe expands?	it becomes irrelevant	it decreases	it is unchanged	it increases	Figure below shows a simple diagram of the expanding universe. Imagine a balloon covered with tiny dots. When you blow up the balloon, the rubber stretches. The dots slowly move away from each other as the space between them increases. In an expanding universe, the space between galaxies is expanding. We see this as the other galaxies moving away from us. We also see that galaxies farther away from us move away faster than nearby galaxies.
Rainwater absorbs carbon dioxide (co 2 ) as it falls. the co 2 combines with water to form what?	methane gas	carbon monoxide	nitrate acid	carbonic acid	Rainwater absorbs carbon dioxide (CO 2 ) as it falls. The CO 2 combines with water to form carbonic acid. The slightly acidic water is especially good at dissolving the rock limestone. Groundwater creates landforms by dissolving away rock.
Most molecular compounds that have a mass similar to water are in what state of matter at room temperature?	vapor	solid	liquid	gas	The hydrogen bonding that occurs in water leads to some unusual, but very important properties. Most molecular compounds that have a mass similar to water are gases at room temperature. Because of the strong hydrogen bonds, water molecules are able to stay condensed in the liquid state. The Figure below shows how the bent shape and two hydrogen atoms per molecule allows each water molecule to be able to hydrogen bond to two other molecules.
What do you call the movement of molecules across a membrane without the input of energy?	active transport	obvious transport	reactive transport	passive transport	Recall that the cell membrane is semipermeable. It does not allow everything to pass through. Some molecules can pass easily through your cell membranes, while others have more difficulty. Sometimes molecules need the help of special transport proteins to move across the cell membrane. Some molecules even need an input of energy to help get them across the cell membrane. The movement of molecules across a membrane without the input of energy is known as passive transport . When energy (ATP) is needed, the movement is known as active transport . Active transport moves molecules against their concentration gradient, from an area of low concentration to an area of high concentration.
Opposite charges attract and like charges do what?	impede	nothing	rebound	repulse	Opposite charges attract and like charges repulse.
What molecules are usually insoluble in water?	ions	polar	acids	non-polar	Non-polar molecules are usually insoluble in water.
What occurs when there is a sudden discharge of static electricity between a cloud and the ground?	rain	updraft	wind	lightning	Lightning occurs when there is a sudden discharge of static electricity between a cloud and the ground.
If citrate accumulates in mitochondria, some of it passes into where and inhibits phosphofructokinase?	pores	Golgi apparatus	epidermis	cytosol
For most of a star’s life, hydrogen atoms fuse to form what?	gas atoms	neon atoms	ionic atoms	helium atoms	For most of a star’s life, hydrogen atoms fuse to form helium atoms. A star like this is a main sequence star . The hotter a main sequence star is, the brighter it is. A star remains on the main sequence as long as it is fusing hydrogen to form helium.
What two ways do channels respond during membrane depolarization?	typically and sequentially	sequentially and identically	independently and typically	independently and sequentially
What kind of compound, contained in coffee and alcohol, increases urine volume?	additive	anabolic	acid	diuretic	Diuretics and Fluid Volume A diuretic is a compound that increases urine volume. Three familiar drinks contain diuretic compounds: coffee, tea, and alcohol. The caffeine in coffee and tea works by promoting vasodilation in the nephron, which increases GFR. Alcohol increases GFR by inhibiting ADH release from the posterior pituitary, resulting in less water recovery by the collecting duct. In cases of high blood pressure, diuretics may be prescribed to reduce blood volume and, thereby, reduce blood pressure. The most frequently prescribed anti-hypertensive diuretic is hydrochlorothiazide. It inhibits the Na+/ Cl– symporter in the DCT and collecting duct. The result is a loss of Na+ with water following passively by osmosis. Osmotic diuretics promote water loss by osmosis. An example is the indigestible sugar mannitol, which is most often administered to reduce brain swelling after head injury. However, it is not the only sugar that can produce a diuretic effect. In cases of poorly controlled diabetes mellitus, glucose levels exceed the capacity of the tubular glucose symporters, resulting in glucose in the urine. The unrecovered glucose becomes a powerful osmotic diuretic. Classically, in the days before glucose could be detected in the blood and urine, clinicians identified diabetes mellitus by the three Ps: polyuria (diuresis), polydipsia (increased thirst), and polyphagia (increased hunger).
In mammals what does the zona pellucida protect?	fetus	testes	sperm	egg	Fertilization Fertilization, pictured in Figure 43.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. The egg and sperm each contain one set of chromosomes. To ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. In mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. When a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. In placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma.
What type of vertebrates control body temperature to just a limited extent from the outside by changing behavior?	mimetic	etheric	endothermic	ectothermic	Early vertebrates were ectothermic. Ectothermy means controlling body temperature to just a limited extent from the outside by changing behavior. For example, an ectotherm might stay in the shade to keep cool on a hot, sunny day. On a cold day, an ectotherm might bask in the sun to warm up, like the snake in Figure below . Almost all living fish, amphibians, and reptiles are ectothermic. They can raise or lower their body temperature by their behavior but not by very much. In cold weather, an ectotherm cools down. As its body temperature drops, its metabolism slows down and it becomes inactive.
Worldwide, viruses seem to play a role in what percentage of the cases of human cancer?	5%	20 %	+.15 %	15%
Elements are pure substances that make up what?	Solids	some matter	Objects	all matter	Elements are pure substances that make up all matter, so each one is given a unique name. The names of elements are also represented by unique one-, two-, or three- letter symbols.
What reproductive part is stored in a plant's pollen?	the egg	the gamete	the mimic	the sperm	Plants can also reproduce sexually, but their reproductive organs are different from animals’ gonads. Plants that have flowers have their reproductive parts in the flower. The sperm is contained in the pollen, while the egg is contained in the ovary, deep within the flower. The sperm can reach the egg two different ways:.
Atoms of what element ultimately form in a red supergiant?	coal	gold	steel	iron	In a red supergiant, fusion does not stop. Lighter atoms fuse into heavier atoms. Eventually iron atoms form.
What are the two types of fats?	liquid and solid	thick and thin	full and empty	saturated and unsaturated	Fats may be either saturated or unsaturated. A saturated fat is a fat that consists of triglycerides whose carbon chains consist entirely of carbon-carbon single bonds. Therefore, the carbon chains are saturated with the maximum number of hydrogen atoms possible. An unsaturated fat is a fat that consists of triglycerides whose carbon chains contain one or more carbon-carbon double bonds . A fat with one double bond is called monounsaturated, while a fat with multiple double bonds is called polyunsaturated (see Figure below ).
What structure consists of an outer layer of cells called the trophoblast and an inner cell mass called the embryoblast?	cell wall	nucleus	cytoplasm	blastocyst	Blastocyst. The blastocyst consists of an outer layer of cells called the trophoblast and an inner cell mass called the embryoblast. The blastocyst fluid-filled cavity is also known as the blastocoel or blastocoele.
Metabolic pathways are a series of reactions catalyzed by multiple what?	particles	hormones	vitamins	enzymes	Figure 4.11 Metabolic pathways are a series of reactions catalyzed by multiple enzymes. Feedback inhibition, where the end product of the pathway inhibits an upstream process, is an important regulatory mechanism in cells.
What causes eutrophication to occur?	excess of increased and other nutrients	excess of decreased and other nutrients	excess of carbonate and other nutrients	excess of fertilizers and other nutrients	Fertilizer in runoff leads to algal blooms and dead zones in bodies of water. This type of pollution is called nonpoint-source pollution. Point-source pollution includes waste water from factories and sewage treatment plants. Hot water discharge causes thermal pollution.
What do you call the separation of ions that occurs when a solid ionic compound dissolves?	dissolution	deformation	decomposition	dissociation	An ionic crystal lattice breaks apart when it is dissolved in water. Dissociation is the separation of ions that occurs when a solid ionic compound dissolves. It is important to be able to write dissociation equations. Simply undo the crisscross method that you learned when writing chemical formulas of ionic compounds. The subscripts for the ions in the chemical formulas become the coefficients of the respective ions on the product side of the equation. Shown below are dissociation equations for NaCl, Ca(NO 3 ) 2 , and (NH 4 ) 3 PO 4 .
What is light with wavelengths shorter than visible light called?	radio waves	weathering light	infrared light	ultraviolet light	Light with wavelengths shorter than visible light is called ultraviolet light . The term ultraviolet means “above violet. ” Ultraviolet light is the range of light waves that have shorter wavelengths and higher frequencies than violet light in the visible range of light. With higher frequencies than visible light, ultraviolet light has more energy. It can be used to kill bacteria in food and to sterilize surgical instruments. The human skin also makes vitamin D when it is exposed to ultraviolet light. Vitamin D, in turn, is needed for strong bones and teeth. You can learn more about ultraviolet light and its discovery at this URL: http://www. youtube. com/watch?v=QW5zeVy8aE0.
How much distance can beta particles travel through air?	density	centimeters	inches	meter	Beta particles can travel up to a meter through air. They can pass through paper and cloth but not through a sheet of aluminum. They can penetrate and damage tissues beneath the skin.
What is created when the warm air at the cold front rises and creates a low pressure cell, causing winds to rush into the low pressure?	Wind pressure	Tornado	Hurricane	rising air column	The warm air at the cold front rises and creates a low pressure cell. Winds rush into the low pressure. This creates a rising column of air. The air twists, rotating counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Since the rising air is moist, rain or snow falls.
People with osteoporosis have an increase risk of what?	weight loss	cancer	muscle loss	bone fractures	People with osteoporosis have an increased risk of bone fractures. A bone fracture is a crack or break in bone. Even if you have healthy bones, you may fracture a bone if too much stress is placed on it. This could happen in a car crash or while playing a sport. Wearing a seatbelt when you ride in a motor vehicle and wearing safety gear when you play sports may help prevent bone fractures.
What is the main artery of the systematic circulation called?	carotid	femoral	subclavian	aorta	Blood Vessels The blood from the heart is carried through the body by a complex network of blood vessels (Figure 16.12). Arteries take blood away from the heart. The main artery of the systemic circulation is the aorta; it branches into major arteries that take blood to different limbs and organs. The aorta and arteries near the heart have heavy but elastic walls that respond to and smooth out the pressure differences caused by the beating heart. Arteries farther away from the heart have more muscle tissue in their walls that can constrict to affect flow rates of blood. The major arteries diverge into minor arteries, and then smaller vessels called arterioles, to reach more deeply into the muscles and organs of the body. Arterioles diverge into capillary beds. Capillary beds contain a large number, 10’s to 100’s of capillaries that branch among the cells of the body. Capillaries are narrow-diameter tubes that can fit single red blood cells and are the sites for the exchange of nutrients, waste, and oxygen with tissues at the cellular level. Fluid also leaks from the blood into the interstitial space from the capillaries. The capillaries converge again into venules that connect to minor veins that finally connect to.
The length that an object has travelled in one or multiple directions can also be called what?	range	axis	velocity	distance	The length traveled by an object moving in any direction or even changing direction is called distance.
In animals, what process occurs only in germ cells, which are in the ovaries or testes?	reproduction	mitosis	electrolysis	meiosis
Which theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring?	molecular orbital theory	hybrid orbital theory	covalent bond theory	valence bond theory	Valence bond theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring. Three valence electrons in the sp2 hybrid orbitals of each carbon atom and the valence electron of each hydrogen atom form the framework of σ bonds in the benzene molecule. The fourth valence electron of each carbon atom is shared with an adjacent carbon atom in their unhybridized p orbitals to yield the π bonds. Benzene does not, however, exhibit the characteristics typical of an alkene. Each of the six bonds between its carbon atoms is equivalent and exhibits properties that are intermediate between those of a C–C single bond and a C = C double bond. To represent this unique bonding, structural formulas for benzene and its derivatives are typically drawn with single bonds between the carbon atoms and a circle within the ring as shown in Figure 20.11.
What type of carbon dioxide levels have been rising for the past several decades?	subatomic	magnetic	aqueous	atmospheric	Atmospheric carbon dioxide levels have been rising for the past several decades.
Freezing rain that falls from the sky is also called?	fog	snowfall	hail	sleet
Do waves move faster when particles are close to each other or far away?	open	unaffected	far away	close	The speed of most waves depends on the medium through which they are traveling. Generally, waves travel fastest through solids and slowest through gases. That’s because particles are closest together in solids and farthest apart in gases. When particles are farther apart, it takes longer for the energy of the disturbance to pass from particle to particle.
Adult bees include workers, a queen and what other type?	builders	laborers	soldiers	drones	Look at the honeybees in Figure below . Honeybees live in colonies that may consist of thousands of individual bees. Generally, there are three types of adult bees in a colony: workers, a queen, and drones.
Name the law that determines as to which rock layers are younger or older than others.	law of apposition	law of gravity	geologic theory	law of superposition	In this lesson, you read how scientists determine the relative ages of sedimentary rock layers. The law of superposition determines which rock layers are younger or older than others.
Since the electric field lines point radially away from the charge, they are perpendicular to what?	magnetic field lines	singularity lines	archetypical lines	equipotential lines	19.4 Equipotential Lines We can represent electric potentials (voltages) pictorially, just as we drew pictures to illustrate electric fields. Of course, the two are related. Consider Figure 19.8, which shows an isolated positive point charge and its electric field lines. Electric field lines radiate out from a positive charge and terminate on negative charges. While we use blue arrows to represent the magnitude and direction of the electric field, we use green lines to represent places where the electric potential is constant. These are called equipotential lines in two dimensions, or equipotential surfaces in three dimensions. The term equipotential is also used as a noun, referring to an equipotential line or surface. The potential for a point charge is the same anywhere on an imaginary sphere of radius r surrounding the charge. This is true since the potential for a point charge is given by V = kQ / r and, thus, has the same value at any point that is a given distance r from the charge. An equipotential sphere is a circle in the two-dimensional view of Figure 19.8. Since the electric field lines point radially away from the charge, they are perpendicular to the equipotential lines.
What are in leaves that function as solar collectors and food factories?	fibroblasts	cellulose	vacuoles	chloroplasts	Leaves are rich in chloroplasts that function as solar collectors and food factories. The first leaves were very small, but leaves became larger over time.
What is the process of producing eggs in the ovary is called?	morphogenesis	gametogenesis	meiosis	oogenesis	The process of producing eggs in the ovary is called oogenesis. Eggs, like sperm, are haploid cells, and their production occurs in several steps that involve different types of cells, as shown in Figure below . You can follow the process of oogenesis in the figure as you read about it below.
What term refers to the deliberate prevention of pregnancy?	abortion	reproduction	cessation	contraception
Homologous chromosomes move toward what poles?	octogonal	interior	parallel	opposite	Homologous chromosomes move toward opposite poles of a dividing cell during.
Why are the stems of many xerophytes fleshy?	collects water	drains water	pressures water	stores water
Most body fluids that you release from your body contain chemicals that kill pathogens. for example, mucus, sweat, tears, and saliva contain enzymes called?	sporozoans	lipids	enzymes	lysozymes	Most body fluids that you release from your body contain chemicals that kill pathogens. For example, mucus, sweat, tears, and saliva contain enzymes called lysozymes that kill pathogens. These enzymes can break down the cell walls of bacteria to kill them.
What is at the top of the mesosphere?	Mesosphere	Troposphere	Stratosphere	mesopause	At the top of the mesosphere is the mesopause. Temperatures here are colder than anywhere else in the atmosphere. They are as low as -100° C (-212° F)! Nowhere on Earth’s surface is that cold.
Yogurt is made from milk fermented with what type of organism?	algae	viruses	yeast	bacteria	Mom the Barbarian. Yogurt is made from milk fermented with bacteria . CC BY 2.0.
What happens to an animal's telomeres as it ages?	multiply	divide	lengthen	shorten	As cells divide, their chromosomes get shorter. This is because the telomeres, the DNA sequences at both ends of a chromosome, lose material every time the DNA is replicated. The older the animal is, the shorter its telomeres will be, because of the number of cell cycles the cells have been through This is a natural part of aging. So, what happens to the clone if its transferred nucleus is already fairly old? Will the shortened telomeres affect its development or lifespan? The answer is still unclear. But starting a new organisms with "old" DNA with shortened telomeres is bound to have some effects, at least in some clones. Some cloned animals may be affected, others may not. Dolly the sheep's chromosomes did have shorter telomere lengths than normal. This means that Dolly's cells were aging faster than the cells from a normal sheep.
Characterized by uncontrolled growth, cancerous cells are also called what?	toxic	abnormal	benign	malignant	Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells. There are over 200 different known cancers that afflict humans.
Historically, malaria has rivaled what as the leading cause of human death by infectious disease?	cancer	heart attack	hepatitis	tuberculosis	Alloys can be one of two general types. In one type, called a substitutional alloy, the various atoms simply replace each other in the crystal structure. In another type, called an interstitial alloy, the smaller atoms such as carbon fit in between the larger atoms in the crystal packing arrangement.
When the number of electrons and the number of protons are equal, the object is what?	static	Negative	Positive	neutral	When the number of electrons and the number of protons are equal, the object is neutral.
The angle of refraction depends on the index of what?	reflection	frequency	vibration	refraction	Refraction is responsible for dispersion in rainbows and many other situations. The angle of refraction depends on the index of refraction, as we saw in The Law of Refraction. We know that the index of refraction n depends on the medium. But for a given medium, n also depends on wavelength. (See Table 25.2. Note that, for a given medium, n increases as wavelength decreases and is greatest for violet light. Thus violet light is bent more than red light, as shown for a prism in Figure 25.23(b), and the light is dispersed into the same sequence of wavelengths as seen in Figure 25.21 and Figure 25.22. Making Connections: Dispersion Any type of wave can exhibit dispersion. Sound waves, all types of electromagnetic waves, and water waves can be dispersed according to wavelength. Dispersion occurs whenever the speed of propagation depends on wavelength, thus separating and spreading out various wavelengths. Dispersion may require special circumstances and can result in spectacular displays such as in the production of a rainbow. This is also true for sound, since all frequencies ordinarily travel at the same speed. If you listen to sound through a long tube, such as a vacuum cleaner hose, you can easily hear it is dispersed by interaction with the tube. Dispersion, in fact, can reveal a great deal about what the wave has encountered that disperses its wavelengths. The dispersion of electromagnetic radiation from outer space, for example, has revealed much about what exists between the stars—the so-called empty space.

Deficiency of what is symptomized by nausea, fatigue and dizziness, and can be triggered by excessive sweating?

calories

impurities

salts

electrolytes

An alkaline battery is a variation on the zinc-carbon dry cell. The alkaline battery has no carbon rod and uses a paste of zinc metal and potassium hydroxide instead of a solid metal anode. The cathode half-reaction is the same, but the anode half-reaction is different.

Most thoracic vertebrae have two facets that articulate with the head of what structure?

pelvic

calf

heart

rib

Thoracic Vertebrae The bodies of the thoracic vertebrae are larger than those of cervical vertebrae (Figure 7.26). The characteristic feature for a typical midthoracic vertebra is the spinous process, which is long and has a pronounced downward angle that causes it to overlap the next inferior vertebra. The superior articular processes of thoracic vertebrae face anteriorly and the inferior processes face posteriorly. These orientations are important determinants for the type and range of movements available to the thoracic region of the vertebral column. Thoracic vertebrae have several additional articulation sites, each of which is called a facet, where a rib is attached. Most thoracic vertebrae have two facets located on the lateral sides of the body, each of which is called a costal facet (costal = “rib”). These are for articulation with the head (end) of a rib. An additional facet is located on the transverse process for articulation with the tubercle of a rib.

Thrombocytes are more commonly known by what name?

droplets

chromosomes

molecules

platelets

Platelets and Coagulation Factors Blood must clot to heal wounds and prevent excess blood loss. Small cell fragments called platelets (thrombocytes) are attracted to the wound site where they adhere by extending many projections and releasing their contents. These contents activate other platelets and also interact with other coagulation factors, which convert fibrinogen, a water-soluble protein present in blood serum into fibrin (a non-water soluble protein), causing the blood to clot. Many of the clotting factors require vitamin K to work, and vitamin K deficiency can lead to problems with blood clotting. Many platelets converge and stick together at the wound site forming a platelet plug (also called a fibrin clot), as illustrated in Figure 40.8b. The plug or clot lasts for a number of days and stops the loss of blood. Platelets are formed from the disintegration of larger cells called megakaryocytes, like that shown in Figure 40.8a. For each megakaryocyte, 2000–3000 platelets are formed with 150,000 to 400,000 platelets present in each cubic millimeter of blood. Each platelet is disc shaped and 2–4 μm in diameter. They contain many small vesicles but do not contain a nucleus.

What is the term for the remains or traces of living organisms?

deposits

remains

ethings

fossils

Fossils are the remains or traces of living organisms.

What type of disease is caused by pathogens?

autoimmune diseases

viral diseases

nervous diseases

infectious diseases

Infectious diseases are diseases that are caused by pathogens. Human pathogens include bacteria, viruses, fungi, and protozoa. Different pathogens spread in different ways. Pathogens may spread through contaminated food or water, sexual contact, droplets in the air from coughs or sneezes, contaminated objects or surfaces, or vectors.

Worms grow to adult size without going through what stage?

growth

egg

development

larval

In some species, the same individual produces both sperm and eggs. But worms mate to exchange sperm, rather than self-fertilizing their own eggs. Fertilized eggs are deposited in a mucous cocoon. Offspring emerge from the cocoon looking like small adults. They grow to adult size without going through a larval stage.

What serves as a first responder to pathogenic threats that bypass natural physical and chemical barriers of the body?

immense immune system

cells immune system

super immune system

innate immune system

CHAPTER SUMMARY 42.1 Innate Immune Response The innate immune system serves as a first responder to pathogenic threats that bypass natural physical and chemical barriers of the body. Using a combination of cellular and molecular attacks, the innate immune system identifies the nature of a pathogen and responds with inflammation, phagocytosis, cytokine release, destruction by NK cells, and/or a complement system. When innate mechanisms are insufficient to clear an infection, the adaptive immune response is informed and mobilized.

Of the three basic types of emissions, which has the highest penetrating power?

chemical radiation

ultraviolet radiation

fluid radiation

gamma radiation

Of the three basic types of emissions, gamma radiation has the highest penetrating power. Thick, high density materials (such as lead) are required to stop gamma emissions. The thickness of the shielding will determine the effectiveness of the protection offered by the lead.

True animals are divided into those with radial versus bilateral styles of what?

magnetic

attracted

molecular

symmetry

27.2 Features Used to Classify Animals Organisms in the animal kingdom are classified based on their body morphology and development. True animals are divided into those with radial versus bilateral symmetry. Generally, the simpler and often non-motile animals display radial symmetry. Animals with radial symmetry are also generally characterized by the development of two embryological germ layers, the endoderm and ectoderm, whereas animals with bilateral symmetry are generally characterized by the development of a third embryological germ layer, the mesoderm. Animals with three germ layers, called triploblasts, are further characterized by the presence or absence of an internal body cavity called a coelom. The presence of a coelom affords many advantages, and animals with a coelom may be termed true coelomates or pseudocoelomates, depending on which tissue gives rise to the coelom. Coelomates are further divided into one of two groups called protostomes and deuterostomes, based on a number of developmental characteristics, including differences in zygote cleavage and method of coelom formation.

While still an early fetus, what is the skeleton made of?

gel

ligament

membrane

cartilage

Early in the development of a human fetus, the skeleton is made entirely of cartilage. The relatively soft cartilage gradually turns into hard bone through ossification . This is a process in which mineral deposits replace cartilage. As shown in Figure below , ossification of long bones, which are found in the arms and legs, begins at the center of the bones and continues toward the ends. By birth, several areas of cartilage remain in the skeleton, including the ends of the long bones. This cartilage grows as the long bones grow, so the bones can keep increasing in length during childhood.

What forms the pathway of water and nutrients from roots to leaves and flower?

the pistil

the stamen

the stigma

the stem

What proteins span the entire plasma membrane?

cytoplasm

sequence

amino acids

transmembrane

Transmembrane proteins span the entire plasma membrane. Their function is mainly to regulate the transport of specific molecules across the membrane. There are two basic types of transmembrane proteins, alpha-helical and beta-barrels, which are discussed in Organic Compounds: Proteins (Advanced) .

Why is blue cheese blue?

fermentation

artificial dye

bacteria

fungus

Stuart Webster. Blue cheese is blue because of the fungus growing throughout it. . CC BY 2.0.

What type of joint are ball-and-socket, hinge, and pivot examples of?

fixed

retractable

artificial

movable

Joints may be immovable, partly movable, or movable. Types of movable joints include ball-and-socket, hinge, and pivot joints.

Are valence electrons attracted more or less strongly when they are farther from the nucleus?

differently

equally

more strongly

less strongly

The reactivity of alkaline Earth metals increases from the top to the bottom of the group. That’s because the atoms get bigger from the top to the bottom, so the valence electrons are farther from the nucleus. When valence electrons are farther from the nucleus, they are attracted less strongly by the nucleus and more easily removed from the atom. This makes the atom more reactive.

What do we call the predictable distribution of molecular speeds found in gas of many molecules?

kemp - boltzmann distribution

mitchell - boltzmann distribution

burns - boltzmann distribution

maxwell-boltzmann distribution

• The motion of individual molecules in a gas is random in magnitude and direction. However, a gas of many molecules has a predictable distribution of molecular speeds, known as the Maxwell-Boltzmann distribution.

Name the simple sugar that is a component of starch.

insulin

Fructose

Splenda

glucose

3.2 | Carbohydrates By the end of this section, you will be able to: • Discuss the role of carbohydrates in cells and in the extracellular materials of animals and plants • Explain the classifications of carbohydrates • List common monosaccharides, disaccharides, and polysaccharides Most people are familiar with carbohydrates, one type of macromolecule, especially when it comes to what we eat. To lose weight, some individuals adhere to “low-carb” diets. Athletes, in contrast, often “carb-load” before important competitions to ensure that they have enough energy to compete at a high level. Carbohydrates are, in fact, an essential part of our diet; grains, fruits, and vegetables are all natural sources of carbohydrates. Carbohydrates provide energy to the body, particularly through glucose, a simple sugar that is a component of starch and an ingredient in many staple foods. Carbohydrates also have other important functions in humans, animals, and plants.

What do vertebrates have which invertebrates do not?

tails

appendages

fangs

backbones

Vertebrates have a backbone, but invertebrates do not. Except for the chordates, all animal phyla consist only of invertebrates. Chordates include both vertebrates and invertebrates.

Occuring throughout the lifespan of the organism, what stages proceed in a certain order?

genetic stages

yearly stages

life effectiveness stages

life cycle stages

The fetus is connected to what by a tube called the umbilical cord?

Fallopian tube

Stomach

Intestines

placenta

The placenta is a spongy mass of blood vessels. Some of the vessels come from the mother. Some come from the fetus. The placenta is attached to the inside of the mother’s uterus. The fetus is connected to the placenta by a tube called the umbilical cord . The cord contains two arteries and a vein. Substances pass back and forth between the mother’s and fetus’s blood through the placenta and cord. Oxygen and nutrients pass from the mother to the fetus. Carbon dioxide passes from the fetus to the mother.

What are most fresh fruits, vegetables, whole grains rich in?

magnesium

calcium

cholesterol

cellulose

What term tells you how quickly the angle changes and can occur in either clockwise or counterclockwise directions?

turning velocity

emit velocity

shift velocity

angular velocity

The angular velocity tells you how quickly the angle changes. In more formal language, the rate of change of , the angular position, is called the angular velocity . The direction of angular velocity is either clockwise or counterclockwise. Analogously, the rate of change of is the angular acceleration .

What term is used to describe how fast a chemical reaction occurs?

velocity

response time

catalysis

reaction rate

How fast a chemical reaction occurs is called the reaction rate . Several factors affect the rate of a given chemical reaction. They include the:.

What is the term for protists that produce spores, such as the toxoplasm?

newborns

protozoans

spermatozoa

sporozoans

The sporozoans are protists that produce spores, such as the toxoplasma . These protists do not move at all. The spores develop into new protists.

Why does neptune's appearance change?

the speed of rotation

the seasons

the changing orbit

turbulent atmosphere

Neptune's appearance changes due to its turbulent atmosphere. Winds are stronger than on any other planet in the solar system. Wind speeds can reach 1,100 km/h (700 mph). This is close to the speed of sound! The rapid winds surprised astronomers. This is because Neptune receives little energy from the Sun to power weather systems. It is not surprising that Neptune is one of the coldest places in the solar system. Temperatures at the top of the clouds are about –218°C (–360°F).

Changing levels of what substances partly explain emotional ups and downs in teens?

enzymes

nutrients

acids

hormones

Many teens have emotional ups and downs. This is at least partly due to their changing hormone levels.

What term refers to larger evolutionary changes that result in new species?

substantial evolution

Microevolution

Potential evolution

macroevolution

Macroevolution refers to larger evolutionary changes that result in new species.

What do you call a lens that causes the light rays to bend away from its axis?

converging lens

optical lens

axilens

diverging lens

• A lens that causes the light rays to bend away from its axis is called a diverging lens. • Ray tracing is the technique of graphically determining the paths that light rays take. • The image in which light rays from one point on the object actually cross at the location of the image and can be projected onto a screen, a piece of film, or the retina of an eye is called a real image. • Thin lens equations are.

Diffusion can occur across a semipermeable membrane, such as the cell membrane, as long as a what exists?

differential

polarity

parity

concentration gradient

Diffusion can occur across a semipermeable membrane, such as the cell membrane, as long as a concentration gradient exists. Molecules will continue to flow in this manner until equilibrium is reached. At equilibrium, there is no longer an area of high concentration or low concentration, and molecules flow equally in both directions across the semipermeable membrane. At equilibrium, equal amounts of a molecule are entering and leaving a cell.

Scientists use what scale to illustrate the order in which events on earth have happened?

cataclysmic time scale

ecological succession

fossil record

geologic time scale

Scientists use the geologic time scale to illustrate the order in which events on Earth have happened.

What will happen if the gas particles inside an inflated balloon suddenly stop moving?

balloon inflates

balloon falls

balloon bursts

balloon deflates

Gas molecules also exert pressure. Earth’s atmosphere exerts pressure because gravity acts on the huge number of gas particles contained in the atmosphere, holding it in place. Pressure is also exerted by a small sample of gas, such as that which is contained in a balloon. Gas pressure is the pressure that results from collisions of gas particles with an object. Inside the balloon, the gas particles collide with the balloon’s inner walls. It is those collisions which keep the balloon inflated. If the gas particles were to suddenly stop moving, the balloon would instantly deflate. The Figure below is an illustration of gas particles exerting pressure inside a container.

What are the major sites of gibberellin production?

stem and roots

flower and fruit

soil and leaves

young roots and leaves

What is required for interconversion between the two forms of an isomeric pair?

turn and reforming

couple and reforming

fixing and reforming

breaking and reforming

Stereoisomers Molecules with the same connectivity but different arrangements of the atoms in space are called stereoisomers. There are two types of stereoisomers: geometric and optical. Geometric isomers differ in the relative position(s) of substituents in a rigid molecule. (For more information on stereoisomers, see Chapter 23 "The ", Section 23.4 "Coordination Compounds". ) Simple rotation about a C–C σ bond in an alkene, for example, cannot occur because of the presence of the π bond. The substituents are therefore rigidly locked into a particular spatial arrangement (part (a) in Figure 2.16 "Some Simple (a) Alkenes, (b) Alkynes, and (c) Cyclic Hydrocarbons"). Thus a carbon–carbon multiple bond, or in some cases a ring, prevents one geometric isomer from being readily converted to the other. The members of an isomeric pair are identified as either cis or trans, and interconversion between the two forms requires breaking and reforming one or more bonds. Because their structural difference causes them to have different physical and chemical properties, cis and trans isomers are actually two distinct chemical compounds.

Bacteria reproduce through what process, where the chromosome copies itself, forming two genetically identical copies?

nuclear fission

multiple fission

residual fission

binary fission

Bacteria reproduce through a process called binary fission . During binary fission, the chromosome copies itself, forming two genetically identical copies. Then, the cell enlarges and divides into two new daughter cells. The two daughter cells are identical to the parent cell. Binary fission can happen very rapidly. Some species of bacteria can double their population in less than ten minutes!.

Water molecules are polar, so they form what type of bonds?

helium

carbon

oxygen

hydrogen

Water molecules are polar, so they form hydrogen bonds. This gives water unique properties, such as a relatively high boiling point, high specific heat, cohesion, adhesion and density.

The cecum is the first part of what structure, where wastes in a liquid state enter from the small intestine?

appendix

duodenum

esophagus

large intestine

http://www. explainthatstuff. com/how-geiger-counters-work. html.

What are the "levels" in a food chain or web called?

gauges

parts

root

trophic

Energy is passed up a food chain or web from lower to higher trophic levels. However, generally only about 10 percent of the energy at one level is available to the next level. This is represented by the ecological pyramid in Figure below . What happens to the other 90 percent of energy? It is used for metabolic processes or given off to the environment as heat. This loss of energy explains why there are rarely more than four trophic levels in a food chain or web. Sometimes there may be a fifth trophic level, but usually there’s not enough energy left to support any additional levels.

Are bones considered living or dead tissues?

dead

decaying

decomposing

living

From seeing a skeleton, you might think that bones are just dead, hollow structures. But in a living person, those hollow spaces are full of living cells. Bones have a blood supply and nerves. Bones are a living tissue.

What forms when water in the atmosphere condenses on dust particles suspended in the air?

wind

hail

snow

clouds

What are the two types of fermentation?

lactic acid and fermaldehyde

acetic and anhydrous

alcoholic and alchemical

lactic acid and alcoholic

There are two types of fermentation: lactic acid fermentation and alcoholic fermentation. Both types of fermentation are described below. You can also watch animations of both types at this link: http://www. cst. cmich. edu/users/schul1te/animations/fermentation. swf .

Aging occurs as cells lose their ability to do what?

join

grow

build

divide

During early adulthood, people form intimate relationships and start careers. Serious health problems start showing up in middle adulthood and old age. Aging occurs as cells lose their ability to divide.

What is it called when liquid water falls from the sky?

erosion

sedimentation

water cycling

precipitation

Applying a pressure greater than the osmotic pressure of a solution will do what?

normal osmosis

ultrafiltration

osmosis

reverse osmosis

Figure 11.26 Applying a pressure greater than the osmotic pressure of a solution will reverse osmosis. Solvent molecules from the solution are pushed into the pure solvent.

The molecule pictured above is thyroxine, a compound produced by which gland?

gallbladder

stomach

kidney

thyroid

The molecule pictured above is thyroxine, a compound produced by the thyroid gland. This molecule regulates how the body uses energy. In a condition known as hypothyroidism, the thyroid makes less thyroxine than normal. A person with this disease feels tired all the time and often puts on weight. Treatment with thyroid hormone supplements takes care of the problem.

Birds generally practice what kind of relationship, with both parents helping to care for the young?

homologous

carnivorous

synonomous

monogamous

Birds generally are monogamous, and both parents help to care for the young.

Gravitropism ensures that roots grow into the soil and that shoots grow toward what?

the south pole

the north pole

trees

sunlight

Plant Responses to Gravity Whether or not they germinate in the light or in total darkness, shoots usually sprout up from the ground, and roots grow downward into the ground. A plant laid on its side in the dark will send shoots upward when given enough time. Gravitropism ensures that roots grow into the soil and that shoots grow toward sunlight. Growth of the shoot apical tip upward is called negative gravitropism, whereas growth of the roots downward is called positive gravitropism. Amyloplasts (also known as statoliths) are specialized plastids that contain starch granules and settle downward in response to gravity. Amyloplasts are found in shoots and in specialized cells of the root cap. When a plant is tilted, the statoliths drop to the new bottom cell wall. A few hours later, the shoot or root will show growth in the new vertical direction. The mechanism that mediates gravitropism is reasonably well understood. When amyloplasts settle to the bottom of the gravity-sensing cells in the root or shoot, they physically contact the endoplasmic reticulum (ER), causing the release of calcium ions from inside the ER. This calcium signaling in the cells causes polar transport of the plant hormone IAA to.

What is the mass of one mole of any given substance?

solute mass

atomic mass

protons mass

molar mass

Molar mass is the mass of one mole of any given substance.

The corona surrounds which major object in our solar system?

Jupiter

Neptune

Earth's moon

the sun

The corona is the halo around the Sun.

Respiration that occurs in the cells is called?

biological respiration

electromagnetic respiration

plasma respiration

cellular respiration

Another kind of respiration takes place within body cells. This kind of respiration is called cellular respiration. It’s the process in which cells obtain energy by “burning” glucose. Both types of respiration are connected. Cellular respiration uses oxygen and produces carbon dioxide. Respiration by the respiratory system supplies the oxygen needed for cellular respiration. It also removes the carbon dioxide produced by cellular respiration.

Metabolism is an emergent property of life that arises from orderly interactions between what?

nutrients

tissues

body systems

molecules

During cellular respiration, carbons from the glucose molecule are changed back into what gas?

liquid dioxide

deformation dioxide

carbon monoxide

carbon dioxide

In biological systems, matter is continuously changing states as well. For example, carbon in the form of the gas carbon dioxide is changed into glucose, a solid. This change, of course, occurs during photosynthesis. During cellular respiration, carbons from the glucose molecule are changed back into the carbon dioxide gas.

How does the distance between galaxies change as the universe expands?

it becomes irrelevant

it decreases

it is unchanged

it increases

Figure below shows a simple diagram of the expanding universe. Imagine a balloon covered with tiny dots. When you blow up the balloon, the rubber stretches. The dots slowly move away from each other as the space between them increases. In an expanding universe, the space between galaxies is expanding. We see this as the other galaxies moving away from us. We also see that galaxies farther away from us move away faster than nearby galaxies.

Rainwater absorbs carbon dioxide (co 2 ) as it falls. the co 2 combines with water to form what?

methane gas

carbon monoxide

nitrate acid

carbonic acid

Rainwater absorbs carbon dioxide (CO 2 ) as it falls. The CO 2 combines with water to form carbonic acid. The slightly acidic water is especially good at dissolving the rock limestone. Groundwater creates landforms by dissolving away rock.

Most molecular compounds that have a mass similar to water are in what state of matter at room temperature?

vapor

solid

liquid

gas

The hydrogen bonding that occurs in water leads to some unusual, but very important properties. Most molecular compounds that have a mass similar to water are gases at room temperature. Because of the strong hydrogen bonds, water molecules are able to stay condensed in the liquid state. The Figure below shows how the bent shape and two hydrogen atoms per molecule allows each water molecule to be able to hydrogen bond to two other molecules.

What do you call the movement of molecules across a membrane without the input of energy?

active transport

obvious transport

reactive transport

passive transport

Recall that the cell membrane is semipermeable. It does not allow everything to pass through. Some molecules can pass easily through your cell membranes, while others have more difficulty. Sometimes molecules need the help of special transport proteins to move across the cell membrane. Some molecules even need an input of energy to help get them across the cell membrane. The movement of molecules across a membrane without the input of energy is known as passive transport . When energy (ATP) is needed, the movement is known as active transport . Active transport moves molecules against their concentration gradient, from an area of low concentration to an area of high concentration.

Opposite charges attract and like charges do what?

impede

nothing

rebound

repulse

Opposite charges attract and like charges repulse.

What molecules are usually insoluble in water?

ions

polar

acids

non-polar

Non-polar molecules are usually insoluble in water.

What occurs when there is a sudden discharge of static electricity between a cloud and the ground?

rain

updraft

wind

lightning

Lightning occurs when there is a sudden discharge of static electricity between a cloud and the ground.

If citrate accumulates in mitochondria, some of it passes into where and inhibits phosphofructokinase?

pores

Golgi apparatus

epidermis

cytosol

For most of a star’s life, hydrogen atoms fuse to form what?

gas atoms

neon atoms

ionic atoms

helium atoms

For most of a star’s life, hydrogen atoms fuse to form helium atoms. A star like this is a main sequence star . The hotter a main sequence star is, the brighter it is. A star remains on the main sequence as long as it is fusing hydrogen to form helium.

What two ways do channels respond during membrane depolarization?

typically and sequentially

sequentially and identically

independently and typically

independently and sequentially

What kind of compound, contained in coffee and alcohol, increases urine volume?

additive

anabolic

acid

diuretic

Diuretics and Fluid Volume A diuretic is a compound that increases urine volume. Three familiar drinks contain diuretic compounds: coffee, tea, and alcohol. The caffeine in coffee and tea works by promoting vasodilation in the nephron, which increases GFR. Alcohol increases GFR by inhibiting ADH release from the posterior pituitary, resulting in less water recovery by the collecting duct. In cases of high blood pressure, diuretics may be prescribed to reduce blood volume and, thereby, reduce blood pressure. The most frequently prescribed anti-hypertensive diuretic is hydrochlorothiazide. It inhibits the Na+/ Cl– symporter in the DCT and collecting duct. The result is a loss of Na+ with water following passively by osmosis. Osmotic diuretics promote water loss by osmosis. An example is the indigestible sugar mannitol, which is most often administered to reduce brain swelling after head injury. However, it is not the only sugar that can produce a diuretic effect. In cases of poorly controlled diabetes mellitus, glucose levels exceed the capacity of the tubular glucose symporters, resulting in glucose in the urine. The unrecovered glucose becomes a powerful osmotic diuretic. Classically, in the days before glucose could be detected in the blood and urine, clinicians identified diabetes mellitus by the three Ps: polyuria (diuresis), polydipsia (increased thirst), and polyphagia (increased hunger).

In mammals what does the zona pellucida protect?

fetus

testes

sperm

egg

Fertilization Fertilization, pictured in Figure 43.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. The egg and sperm each contain one set of chromosomes. To ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. In mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. When a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. In placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma.

What type of vertebrates control body temperature to just a limited extent from the outside by changing behavior?

mimetic

etheric

endothermic

ectothermic

Early vertebrates were ectothermic. Ectothermy means controlling body temperature to just a limited extent from the outside by changing behavior. For example, an ectotherm might stay in the shade to keep cool on a hot, sunny day. On a cold day, an ectotherm might bask in the sun to warm up, like the snake in Figure below . Almost all living fish, amphibians, and reptiles are ectothermic. They can raise or lower their body temperature by their behavior but not by very much. In cold weather, an ectotherm cools down. As its body temperature drops, its metabolism slows down and it becomes inactive.

Worldwide, viruses seem to play a role in what percentage of the cases of human cancer?

5%

20 %

+.15 %

15%

Elements are pure substances that make up what?

Solids

some matter

Objects

all matter

Elements are pure substances that make up all matter, so each one is given a unique name. The names of elements are also represented by unique one-, two-, or three- letter symbols.

What reproductive part is stored in a plant's pollen?

the egg

the gamete

the mimic

the sperm

Plants can also reproduce sexually, but their reproductive organs are different from animals’ gonads. Plants that have flowers have their reproductive parts in the flower. The sperm is contained in the pollen, while the egg is contained in the ovary, deep within the flower. The sperm can reach the egg two different ways:.

Atoms of what element ultimately form in a red supergiant?

coal

gold

steel

iron

In a red supergiant, fusion does not stop. Lighter atoms fuse into heavier atoms. Eventually iron atoms form.

What are the two types of fats?

liquid and solid

thick and thin

full and empty

saturated and unsaturated

Fats may be either saturated or unsaturated. A saturated fat is a fat that consists of triglycerides whose carbon chains consist entirely of carbon-carbon single bonds. Therefore, the carbon chains are saturated with the maximum number of hydrogen atoms possible. An unsaturated fat is a fat that consists of triglycerides whose carbon chains contain one or more carbon-carbon double bonds . A fat with one double bond is called monounsaturated, while a fat with multiple double bonds is called polyunsaturated (see Figure below ).

What structure consists of an outer layer of cells called the trophoblast and an inner cell mass called the embryoblast?

cell wall

nucleus

cytoplasm

blastocyst

Blastocyst. The blastocyst consists of an outer layer of cells called the trophoblast and an inner cell mass called the embryoblast. The blastocyst fluid-filled cavity is also known as the blastocoel or blastocoele.

Metabolic pathways are a series of reactions catalyzed by multiple what?

particles

hormones

vitamins

enzymes

Figure 4.11 Metabolic pathways are a series of reactions catalyzed by multiple enzymes. Feedback inhibition, where the end product of the pathway inhibits an upstream process, is an important regulatory mechanism in cells.

What causes eutrophication to occur?

excess of increased and other nutrients

excess of decreased and other nutrients

excess of carbonate and other nutrients

excess of fertilizers and other nutrients

Fertilizer in runoff leads to algal blooms and dead zones in bodies of water. This type of pollution is called nonpoint-source pollution. Point-source pollution includes waste water from factories and sewage treatment plants. Hot water discharge causes thermal pollution.

What do you call the separation of ions that occurs when a solid ionic compound dissolves?

dissolution

deformation

decomposition

dissociation

An ionic crystal lattice breaks apart when it is dissolved in water. Dissociation is the separation of ions that occurs when a solid ionic compound dissolves. It is important to be able to write dissociation equations. Simply undo the crisscross method that you learned when writing chemical formulas of ionic compounds. The subscripts for the ions in the chemical formulas become the coefficients of the respective ions on the product side of the equation. Shown below are dissociation equations for NaCl, Ca(NO 3 ) 2 , and (NH 4 ) 3 PO 4 .

What is light with wavelengths shorter than visible light called?

radio waves

weathering light

infrared light

ultraviolet light

Light with wavelengths shorter than visible light is called ultraviolet light . The term ultraviolet means “above violet. ” Ultraviolet light is the range of light waves that have shorter wavelengths and higher frequencies than violet light in the visible range of light. With higher frequencies than visible light, ultraviolet light has more energy. It can be used to kill bacteria in food and to sterilize surgical instruments. The human skin also makes vitamin D when it is exposed to ultraviolet light. Vitamin D, in turn, is needed for strong bones and teeth. You can learn more about ultraviolet light and its discovery at this URL: http://www. youtube. com/watch?v=QW5zeVy8aE0.

How much distance can beta particles travel through air?

density

centimeters

inches

meter

Beta particles can travel up to a meter through air. They can pass through paper and cloth but not through a sheet of aluminum. They can penetrate and damage tissues beneath the skin.

What is created when the warm air at the cold front rises and creates a low pressure cell, causing winds to rush into the low pressure?

Wind pressure

Tornado

Hurricane

rising air column

The warm air at the cold front rises and creates a low pressure cell. Winds rush into the low pressure. This creates a rising column of air. The air twists, rotating counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Since the rising air is moist, rain or snow falls.

People with osteoporosis have an increase risk of what?

weight loss

cancer

muscle loss

bone fractures

People with osteoporosis have an increased risk of bone fractures. A bone fracture is a crack or break in bone. Even if you have healthy bones, you may fracture a bone if too much stress is placed on it. This could happen in a car crash or while playing a sport. Wearing a seatbelt when you ride in a motor vehicle and wearing safety gear when you play sports may help prevent bone fractures.

What is the main artery of the systematic circulation called?

carotid

femoral

subclavian

aorta

Blood Vessels The blood from the heart is carried through the body by a complex network of blood vessels (Figure 16.12). Arteries take blood away from the heart. The main artery of the systemic circulation is the aorta; it branches into major arteries that take blood to different limbs and organs. The aorta and arteries near the heart have heavy but elastic walls that respond to and smooth out the pressure differences caused by the beating heart. Arteries farther away from the heart have more muscle tissue in their walls that can constrict to affect flow rates of blood. The major arteries diverge into minor arteries, and then smaller vessels called arterioles, to reach more deeply into the muscles and organs of the body. Arterioles diverge into capillary beds. Capillary beds contain a large number, 10’s to 100’s of capillaries that branch among the cells of the body. Capillaries are narrow-diameter tubes that can fit single red blood cells and are the sites for the exchange of nutrients, waste, and oxygen with tissues at the cellular level. Fluid also leaks from the blood into the interstitial space from the capillaries. The capillaries converge again into venules that connect to minor veins that finally connect to.

The length that an object has travelled in one or multiple directions can also be called what?

range

axis

velocity

distance

The length traveled by an object moving in any direction or even changing direction is called distance.

In animals, what process occurs only in germ cells, which are in the ovaries or testes?

reproduction

mitosis

electrolysis

meiosis

Which theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring?

molecular orbital theory

hybrid orbital theory

covalent bond theory

valence bond theory

Valence bond theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring. Three valence electrons in the sp2 hybrid orbitals of each carbon atom and the valence electron of each hydrogen atom form the framework of σ bonds in the benzene molecule. The fourth valence electron of each carbon atom is shared with an adjacent carbon atom in their unhybridized p orbitals to yield the π bonds. Benzene does not, however, exhibit the characteristics typical of an alkene. Each of the six bonds between its carbon atoms is equivalent and exhibits properties that are intermediate between those of a C–C single bond and a C = C double bond. To represent this unique bonding, structural formulas for benzene and its derivatives are typically drawn with single bonds between the carbon atoms and a circle within the ring as shown in Figure 20.11.

What type of carbon dioxide levels have been rising for the past several decades?

subatomic

magnetic

aqueous

atmospheric

Atmospheric carbon dioxide levels have been rising for the past several decades.

Freezing rain that falls from the sky is also called?

fog

snowfall

hail

sleet

Do waves move faster when particles are close to each other or far away?

open

unaffected

far away

close

The speed of most waves depends on the medium through which they are traveling. Generally, waves travel fastest through solids and slowest through gases. That’s because particles are closest together in solids and farthest apart in gases. When particles are farther apart, it takes longer for the energy of the disturbance to pass from particle to particle.

Adult bees include workers, a queen and what other type?

builders

laborers

soldiers

drones

Look at the honeybees in Figure below . Honeybees live in colonies that may consist of thousands of individual bees. Generally, there are three types of adult bees in a colony: workers, a queen, and drones.

Name the law that determines as to which rock layers are younger or older than others.

law of apposition

law of gravity

geologic theory

law of superposition

In this lesson, you read how scientists determine the relative ages of sedimentary rock layers. The law of superposition determines which rock layers are younger or older than others.

Since the electric field lines point radially away from the charge, they are perpendicular to what?

magnetic field lines

singularity lines

archetypical lines

equipotential lines

19.4 Equipotential Lines We can represent electric potentials (voltages) pictorially, just as we drew pictures to illustrate electric fields. Of course, the two are related. Consider Figure 19.8, which shows an isolated positive point charge and its electric field lines. Electric field lines radiate out from a positive charge and terminate on negative charges. While we use blue arrows to represent the magnitude and direction of the electric field, we use green lines to represent places where the electric potential is constant. These are called equipotential lines in two dimensions, or equipotential surfaces in three dimensions. The term equipotential is also used as a noun, referring to an equipotential line or surface. The potential for a point charge is the same anywhere on an imaginary sphere of radius r surrounding the charge. This is true since the potential for a point charge is given by V = kQ / r and, thus, has the same value at any point that is a given distance r from the charge. An equipotential sphere is a circle in the two-dimensional view of Figure 19.8. Since the electric field lines point radially away from the charge, they are perpendicular to the equipotential lines.

What are in leaves that function as solar collectors and food factories?

fibroblasts

cellulose

vacuoles

chloroplasts

Leaves are rich in chloroplasts that function as solar collectors and food factories. The first leaves were very small, but leaves became larger over time.

What is the process of producing eggs in the ovary is called?

morphogenesis

gametogenesis

meiosis

oogenesis

The process of producing eggs in the ovary is called oogenesis. Eggs, like sperm, are haploid cells, and their production occurs in several steps that involve different types of cells, as shown in Figure below . You can follow the process of oogenesis in the figure as you read about it below.

What term refers to the deliberate prevention of pregnancy?

abortion

reproduction

cessation

contraception

Homologous chromosomes move toward what poles?

octogonal

interior

parallel

opposite

Homologous chromosomes move toward opposite poles of a dividing cell during.

Why are the stems of many xerophytes fleshy?

collects water

drains water

pressures water

stores water

Most body fluids that you release from your body contain chemicals that kill pathogens. for example, mucus, sweat, tears, and saliva contain enzymes called?

sporozoans

lipids

enzymes

lysozymes

Most body fluids that you release from your body contain chemicals that kill pathogens. For example, mucus, sweat, tears, and saliva contain enzymes called lysozymes that kill pathogens. These enzymes can break down the cell walls of bacteria to kill them.

What is at the top of the mesosphere?

Mesosphere

Troposphere

Stratosphere

mesopause

At the top of the mesosphere is the mesopause. Temperatures here are colder than anywhere else in the atmosphere. They are as low as -100° C (-212° F)! Nowhere on Earth’s surface is that cold.

Yogurt is made from milk fermented with what type of organism?

algae

viruses

yeast

bacteria

Mom the Barbarian. Yogurt is made from milk fermented with bacteria . CC BY 2.0.

What happens to an animal's telomeres as it ages?

multiply

divide

lengthen

shorten

As cells divide, their chromosomes get shorter. This is because the telomeres, the DNA sequences at both ends of a chromosome, lose material every time the DNA is replicated. The older the animal is, the shorter its telomeres will be, because of the number of cell cycles the cells have been through This is a natural part of aging. So, what happens to the clone if its transferred nucleus is already fairly old? Will the shortened telomeres affect its development or lifespan? The answer is still unclear. But starting a new organisms with "old" DNA with shortened telomeres is bound to have some effects, at least in some clones. Some cloned animals may be affected, others may not. Dolly the sheep's chromosomes did have shorter telomere lengths than normal. This means that Dolly's cells were aging faster than the cells from a normal sheep.

Characterized by uncontrolled growth, cancerous cells are also called what?

toxic

abnormal

benign

malignant

Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells. There are over 200 different known cancers that afflict humans.

Historically, malaria has rivaled what as the leading cause of human death by infectious disease?

cancer

heart attack

hepatitis

tuberculosis

Alloys can be one of two general types. In one type, called a substitutional alloy, the various atoms simply replace each other in the crystal structure. In another type, called an interstitial alloy, the smaller atoms such as carbon fit in between the larger atoms in the crystal packing arrangement.

When the number of electrons and the number of protons are equal, the object is what?

static

Negative

Positive

neutral

When the number of electrons and the number of protons are equal, the object is neutral.

The angle of refraction depends on the index of what?

reflection

frequency

vibration

refraction

Refraction is responsible for dispersion in rainbows and many other situations. The angle of refraction depends on the index of refraction, as we saw in The Law of Refraction. We know that the index of refraction n depends on the medium. But for a given medium, n also depends on wavelength. (See Table 25.2. Note that, for a given medium, n increases as wavelength decreases and is greatest for violet light. Thus violet light is bent more than red light, as shown for a prism in Figure 25.23(b), and the light is dispersed into the same sequence of wavelengths as seen in Figure 25.21 and Figure 25.22. Making Connections: Dispersion Any type of wave can exhibit dispersion. Sound waves, all types of electromagnetic waves, and water waves can be dispersed according to wavelength. Dispersion occurs whenever the speed of propagation depends on wavelength, thus separating and spreading out various wavelengths. Dispersion may require special circumstances and can result in spectacular displays such as in the production of a rainbow. This is also true for sound, since all frequencies ordinarily travel at the same speed. If you listen to sound through a long tube, such as a vacuum cleaner hose, you can easily hear it is dispersed by interaction with the tube. Dispersion, in fact, can reveal a great deal about what the wave has encountered that disperses its wavelengths. The dispersion of electromagnetic radiation from outer space, for example, has revealed much about what exists between the stars—the so-called empty space.