BIO REVIEW 2

171) Which of the following is a characteristic of squamous epithelium? A) lining or covering tissue B) flattened cells C) adhere to one another D) may be found in multiple layers E) All of the above are characteristics of squamous epithelium.

171) E Squamous epithelium is composed of flat, tile-like cells and may occur in multiple layers as in the epidermis of the skin. As with all epithelial cells, it either lines cavities or covers surfaces and cells are attached to neighboring cells, forming an effective barrier.

172) What is the distinctive characteristic of connective tissue? A) flat, interconnected cells B) presence of a matrix C) presence of axons D) contractile ability E) being hard and mineralized

172) B Connective tissue types are widely varied in form and function but all have cells separated by a matrix. The matrix of bone tissue is hard and mineralized but other connective tissues have liquid, fiber filled, or a gel-like matrix.

173) What system removes waste products from the blood and maintains water balance? A) cardiovascular B) urinary C) respiratory D) lymphatic E) skeletal

173) B The urinary system filters blood, removing waste products and producing urine in the process. The urinary system also helps maintain the water balance of the body by producing more or less concentrated urine.

174) Movement of body parts directly requires the A) muscular system and skeletal system. B) nervous system and endocrine system. C) skeletal system and digestive system. D) muscular system and cardiovascular system. E) endocrine system and nervous system.

174) A The nervous system is involved in the stimulation and control of movement, but it is the muscular system along with the skeletal system that actually moves the body. Muscles are attached to bones by tendons and generate force causing the bones to move relative to each other.

175) Which body system is needed for the exchange of oxygen and carbon dioxide? A) respiratory B) integumentary C) digestive D) urinary E) muscular

175) A The primary function of the respiratory system is to bring oxygen into the body and get rid of carbon dioxide. The exchange occurs between air in the lungs and the blood.

176) Which body system produces red blood cells? A) cardiovascular B) lymphatic C) skeletal D) muscular E) endocrine

176) C Even though blood is considered part of the cardiovascular system, blood cells are produced in the red bone marrow of the skeletal system.

177) Which body system and its organs are incorrectly matched? A) digestive - mouth, stomach, intestines B) lymphatic - thymus, vessels, nodes C) endocrine - mouth, lungs, pituitary D) reproductive - ovaries, testes, uterus E) cardiovascular - heart, blood, blood vessels

177) C The endocrine system contains hormone-producing glands such as the pituitary, thyroid, and adrenal glands. The mouth is usually considered part of the digestive system and the lungs are part of the respiratory system.

178) Which of the following lists the types of connective tissue from least rigid to most rigid? A) hyaline cartilage - loose fibrous - bone - blood B) blood - loose fibrous - hyaline cartilage - bone C) loose fibrous - blood - bone - hyaline cartilage D) bone - hyaline cartilage - blood - loose fibrous E) blood - bone - hyaline cartilage - loose fibrous

178) B The matrix of each type of connective tissue determines its characteristics. Blood has a liquid matrix; loose fibrous tissue has a fibrous matrix; cartilage has a solid but flexible matrix; the matrix of bone is mineralized.

179) If damaged, which tissue type will not be able to conduct an impulse? A) nervous B) epithelial C) connective D) muscular E) columnar

179) A Nervous tissue is capable of receiving a stimulus and conducting the impulse to another nervous tissue. If it is damaged, it may lose the ability to receive or conduct impulses.

180) A four-chambered heart, veins, arteries, and capillaries are found in A) all closed circulatory systems. B) some closed circulatory systems. C) some open circulatory systems. D) all open circulatory systems. E) mammals only.

180) B Animals with closed circulatory systems have a heart, veins, arteries, and capillaries. Fish have a two-chambered heart, amphibians and some reptiles have three chambers, and other reptiles (crocodilians and birds) and mammals have four chambers.

181) The pulmonary circuit in a closed circulatory system functions in A) nutrient absorption from the intestine. B) gas exchange in the lungs. C) waste disposal in the kidneys. D) creating proper blood pressure. E) distribution of nutrients to the body tissues.

181) B In a closed circulatory system, the pulmonary circuit carries blood to the lungs and back where gas exchange occurs and the systemic circuit carries blood to the body tissues where gases, nutrients, and wastes are exchanged.

182) In an open circulatory system, A) hemolymph enters the heart via ostia. B) blood leaves the heart via venules. C) the heart has two or more chambers. D) nutrients are exchanged across the walls of capillaries. E) blood is pumped into cavities called ventricles.

182) A Animals with open circulatory systems pump blood into sinuses surrounding organs. Once the blood leaves the blood vessels and enters the sinuses or hemocoel, it becomes hemolymph. The hemolymph is sucked back into the heart via holes in the heart called ostia.

183) A major evolutionary change between thefishcirculatory system and the circulatory systemsofamphibians, birds, and mammalians is the presence of a A) separate pulmonary circuit in fish. B) two-chambered heart in amphibians, birds, and mammals. C) double-loop pathway in amphibians, birds, and mammals. D) stronger atria in amphibians, birds, and mammals. E) four-chambered heart in fish.

183) C Fish have a single-loop circulatory system. Blood leaves the ventricle and goes under pressure to the gills and then goes to the body with a lowered blood pressure. In all other vertebrates there is a second loop where blood returns to the heart after going through the lungs and is put back under pressure so that the oxygenated blood goes to the tissues with a greater pressure.

184) In animals with four-chambered hearts, the left ventricle A) is larger as it pumps blood to the entire body. B) is larger as it pumps blood in the pulmonary circuit. C) pumps blood to the lungs. D) pumps blood to both the lungs and the body. E) pumps deoxygenated blood.

184) A The right ventricle pumps blood to the lungs, and the left ventricle, which is larger than the right ventricle, pumps blood to the rest of the body. This arrangement not only provides adequate blood pressure for both the pulmonary and systemic circuits, but also prevents the mixing of oxygenated and deoxygenated blood.

185) Which of the following is a function of blood? A) transportsubstances B) defend the body against infection C) regulate bodytemperature D) form clots E) All are functions of blood.

185) E The blood of mammals helps maintain their homeostasis. Blood has numerous functions: 1. It transports substances to and from the capillaries, where exchange with tissue fluid takes place. 2. It helps defend the body against invasion by pathogens (e.g., disease-causing viruses and bacteria). 3. It helps regulate body temperature. 4. It forms clots, preventing a potentially life-threatening loss of blood.

186) Which organism has an open circulatory system? A) grasshopper B) frog C) eagle D) human E) shark

186) A The grasshopper is an example of an invertebrate animal that has an open circulatory system, meaning that the blood is not always confined to the blood vessels. A tubular heart pumps a fluid called hemolymph through a network of channels and cavities in the body.

187) Which of the following statements is true about the majority of arteries in the body? A) Arteries transport blood toward the heart and contain a thick wall of smooth muscle. B) Arteries transport blood toward the heart and contain a thin wall of smooth muscle. C) Arteries transportblood away from the heart and contain a thick wall of smooth muscle. D) Arteries transportblood away from the heart and contain a thick wall of skeletal muscle. E) Arteries transportblood away from the heart and contain a thick wall of cardiac muscle.

187) C The majority of arteries will carry blood away from the heart. They also possess a thick wall of smooth muscle that is under voluntary control.

188) Which of the following statements is correct about the function of the pulmonary circulatory system? A) The pulmonarysystem is responsible for adding oxygen and removing carbon dioxide from thered blood cells. B) The systemic systemis responsible for adding oxygen and removing carbon dioxide from the red bloodcells. C) The pulmonarysystem is responsible for adding carbon dioxide and removing oxygen from thered blood cells. D) The pulmonarysystem is responsible for adding oxygen and removing carbon dioxide from thewhite blood cells. E) The pulmonary system is responsible foradding oxygen and removing carbon dioxide from the platelets.

188) A During the pulmonary circuit red blood cells exchange oxygen and carbon dioxide as they are passed through the capillary beds within the lungs.

189) Which of the following features are incorrectly matched with the type of blood vessel in which it is found? A) well-developed middle layer with smooth muscle and elastic tissue - arteries B) narrow, microscopic tubes of endothelium - capillaries C) valves are present insuring one-way flow of blood - veins D) thick, well-developed walls due to the presence of a thick layer of smooth muscle - veins E) formed from capillaries and join to form veins - venules

189) D Arteries have a thick middle layer of smooth muscle and elastic tissue resulting in a greater thickness overall than veins. Veins are flabby due to a thinner middle layer with little smooth muscle. Veins have valves in their interiors, which keep blood from flowing away from the heart. Venules collect blood from capillaries and join together forming veins. Capillaries are the smallest blood vessels, composed of a single layer of epithelium called endothelium.

190) You are a doctor and a patient comes to you for a checkup. He expresses that his father recently had a heart attack brought on by atherosclerosis. He wants to know what he should do to lower his risk of also having a heart attack. Which of the following statements might you make to him? A) Do not be concerned about your weight. B) Keep exercise to a minimum. C) Decrease the amount of fruits and vegetables in your diet. D) Decrease the amount of saturated fat and cholesterol in your diet. E) Smoking does not contribute to your risk.

190) D In order to lower one's risk for heart attack, one should avoid obesity, cigarettes, and diets high in saturated fats and cholesterol. One should exercise regularly and eat plenty of fruits and vegetables.

191) The function of the lymphatic system is to A) collect O 2-rich blood from below the heart and return it to the right atrium. B) carry blood from the heart to the tissues of the body. C) collect tissue fluid and return it to the subclavian veins. D) collect tissue fluid and return it to the aorta. E) collect O 2-poor blood from above the heart and return it to the right atrium.

191) C The lymphatic system supports the cardiovascular system by collecting excess tissue fluid and returning it to the blood in the subclavian veins. Fats move into the lymph capillaries at the small intestine and are returned to the blood with the lymph fluid.

192) Which blood vessel within the systemic circulatory system will connect the digestive tract and the liver? A) hepatic portal vein B) hepatic vein C) pulmonary trunk D) aorta E) renal vein

192) A The venous connection between the digestive system and the liver is the hepatic portal vein. The hepatic portal system collects proteins and sugars and sends them to the liver. The liver modifies substances absorbed and monitors the composition of the blood. The hepatic vein leaves the liver and carries substances from the liver into the rest of the blood supply.

193) The blood vessels to the lungs and back are collectively known as the A) pulmonary circulation. B) systemic circulation. C) lymphatic system. D) portal system. E) oxygen exchange system.

193) A In the double-loop circulation of the human circulatory system, one loop goes to the lungs and back (pulmonary circulation) and the other goes to the rest of the body (systemic circulation).

194) Which one of the following statements is true about animals that do not have circulatory systems? A) They do not have tissues and organs. B) They may rely on diffusion for the transfer of gases, nutrients, and wastes. C) There are no animals without circulatory systems. D) They tend to have large bodies. E) The body cells are typically distant from the source of the oxygen, so the gas has to diffuse through several layers to reach all cells.

194) B Multicellular organisms such as the hydra and planarian have body plans that allow for the use of diffusion to exchange gases, nutrients, and wastes with the environment as well as throughout their bodies. Echinoderms and nematodes accomplish this through fluid in their coelom. All these animals are relatively small with few exceptions, but all have tissues and many have organs and even organ systems. The organization of the bodies of these animals is such that all cells are very close to the sources of oxygen and nutrients.

195) Which of the following is an inaccurate statement about platelets? A) They form clumps in leaks in blood vessels. B) They produce prothrombin activator. C) They contract within a clot. D) They phagocytize pathogens. E) They are actual fragments of a larger type of cell.

195) D Platelets are one of the types of formed elements found in the blood. They are actually fragments of a larger type of cell. They form a plug in the early stages of a wound and are involved in activating the formation of a clot.

196) Taking up fat from digested foods along with excess tissue fluid and returning it to cardiovascular veins is a function of the A) circulatorysystem. B) systemiccircuit. C) lymphaticsystem. D) pulmonarycircuit. E) cardiovasculararteries.

196) C The lymphatic system supports the cardiovascular system by collecting excess tissue fluid and returning it to the blood in the subclavian veins. Fats move into the lymph capillaries at the small intestine and are returned to the blood with the lymph fluid.

197) The vessel that leaves the heart, taking O 2-rich blood to the body, A) is large in diameter with a thick muscle and elastic layer. B) is called the pulmonary trunk. C) has many valves along its length to assist in blood flow. D) is comprised of a single layer of thin epithelial cells. E) is called the superior vena cava.

197) A The major arteries leaving the heart are the pulmonary trunk and the aorta. The pulmonary trunk takes O 2-poor blood to the lungs; the aorta takes O 2-rich blood to the body. Arteries have a thick muscle and elastic layer as compared to veins.

198) Pulmonary arteries take A) O 2-poor blood to the lungs. B) O 2-rich blood to the lungs. C) O 2-rich blood to the body. D) O 2-poor blood to the right atrium. E) O 2-poor blood to the body.

198) A As in all arteries, the pulmonary arteries carry blood away from the heart. These are different from systemic arteries in that they carry O 2-poor blood.

199) Blood in veins is A) moved by the contraction of the muscles in the walls of the veins. B) moved away from the heart by skeletal muscle contraction. C) usually high in oxygen. D) moved away from the heart with the help of the valves within the veins. E) moved toward the heart by skeletal muscle contraction.

199) E Veins are thinner walled than arteries and carry O 2-poor blood under relatively low pressure to the heart. Veins have valves within them so that as the blood is put under pressure by the contraction of skeletal muscle around them, the blood can only move toward the heart.

200) Blood pressure A) is highest when the heart relaxes. B) can decrease because of atherosclerosis. C) can be lowered by the constriction of arterioles. D) is considered high when it is above 100-70 mm Hg. E) contributes to movement of substances from the blood into the tissues.

200) E Blood pressure is the pressure of blood within arteries as a result of the contraction of the heart. Normal blood pressure is 120/80 mm Hg. The constriction of the smooth muscle within arteriole walls can raise blood pressure when it has lowered for some reason. Diseases such as atherosclerosis, which narrows the blood vessel, can result in raised blood pressure. Normal blood pressure is important because it allows for the normal movement of substances into and out of the capillaries.

201) Which of the following is the correct path urine follows from internal structures to outside the body? A) renal cortex - urethra - urinary bladder - ureter B) urinary bladder - renal pelvis - ureter - urethra C) renal pelvis - ureter - urinary bladder - urethra D) ureter - renal pelvis - urinary bladder - urethra E) ureter - urinary bladder - renal pelvis - urethra

201) C After urine leaves the nephron and enters the collecting duct, it passes into the renal pelvis. The ureters drain the pelvis and fill the urinary bladder. The urethra allows urine to pass out of the bladder and be voided.

202) In which structure does urine formation begin? A) collecting duct B) proximal tubule C) nephron loop D) glomerular capsule E) distal tubule

202) D Urine formation begins in the glmoerular capsule where the blood is filtered and the filtrate is first formed. From there, it passes into the proximal tubule, nephron loop, and distal tubule, where substances are secreted into or reabsorbed from the filtrate.

203) During respiration in fish, what percentage of dissolved oxygen is absorbed? A) 100% B) 95-99% C) 80-90% D) 70-80% E) 60-70%

203) C During respiration in fish, the flow of blood in the gill capillaries is opposite the flow of water across the gill surface. This allows the blood to be constantly exposed to water that contains a higher oxygen concentration. This causes 80-90% of the dissolved oxygen to be absorbed by the blood.

204) Which of the following is the correct pathway of air into the lungs to the site of gas exchange? A) nasal cavity -pharynx - larynx - trachea - bronchi - bronchioles - alveoli B) bronchi - pharynx- larynx - trachea - nasal cavity - bronchioles - alveoli C) bronchi - pharynx- trachea - nasal cavity - bronchioles - alveoli - larynx D) nasal cavity -alveoli - bronchioles - bronchi - trachea - larynx - pharynx E) pharynx - trachea- nasal cavity - bronchioles - alveoli - larynx - bronchi

204) A Air enters the nasal cavity and then passes into the pharynx. From the pharynx it passes into the larynx (voice box) and into the trachea. The trachea carries the air into the right and left bronchi which eventually branch into the bronchioles. The bronchioles lead into the alveoli where gas exchange finally occurs.

205) The tracheal system of insects A) helps remove metabolic wastes from their bodies. B) makes a respiratory pigment in their hemolymph unnecessary. C) relies on the expansion and contraction of the body wall to move air into and out of the system. D) is limited to the posterior end of the body. E) digests food and distributes nutrients to the body.

205) B The respiratory system of insects is the tracheal system. It is composed of a system of tubes supported by chitin that branch throughout the body. Air sacs help move air through the system and close to every cell. Because no individual cell is far from the air in the trachea, a respiratory pigment in the hemolymph, the transport fluid of insects, is unnecessary.

206) You are at your cousin's high school graduation party. The only thing good to drink is lemonade. You end up staying at the party for a long time, drinking four large glasses of lemonade. What would you expect to happen to your urine production? A) You will produce an increased amount of dilute urine. B) You will produce an increased amount of concentrated urine. C) You will produce a decreased amount of concentrated urine. D) You will produce a decreased amount of dilute urine. E) You will produce a typical amount of urine; the lemonade will not have any noticeable impact on your urine production.

206) A The kidneys have the ability to adjust the concentration and volume of urine produced based on the amount of fluids in the body. With a large consumption of fluids, such as lemonade, the kidneys will produce a more dilute urine in an increased amount to rid the body of the excess water without losing necessary particles like sodium and chloride.

207) In order for the body to stay in homeostasis, it must maintain the water-salt balance. Which system is responsible for maintaining this feature? A) urinarysystem B) digestivesystem C) respiratorysystem D) cardiovascularsystem E) integumentarysystem

207) A In vertebrate animals, such as humans, the kidneys play an important role in homeostasis. They filter nitrogenous wastes from the blood and are involved in regulating the water-salt balance of the body. In addition, the mammalian kidney helps regulate the pH of blood. To summarize, the following three functions are associated with the kidneys: 1. Excretion of nitrogenous wastes, such as urea and uric acid 2. Maintenance of the water-salt balance of the blood 3. Maintenance of the acid-base balance of the blood

208) Hair within the nose and cilia lining the respiratory tract A) moisten the air before it enters the lungs. B) prevent particles from entering the lungs. C) help oxygen move into the lungs. D) help carbon dioxide leave the lungs. E) help carbon dioxide move into the lungs.

208) B Hair within the nose traps particles before they move farther into the respiratory tract. The cilia lining various parts or the tract move mucus, which has trapped inhaled particles toward the pharynx. This action prevents the particles from entering the lungs.

209) Which of the following is an incorrect match? A) larynx - contains vocal cords B) pharynx - connects nasal and oral cavities to larynx C) sinuses - remove dust particles from the air D) glottis - opening to the larynx E) epiglottis - covers the glottis

209) C The pharynx connects the nasal cavity, oral cavity, and the openings to the esophagus and trachea. The opening to the trachea is the glottis and the epiglottis covers the glottis during swallowing to keep food from entering the trachea. The larynx, located at the top of the trachea, is the voice box and contains the vocal cords. The sinuses are cavities within the skull containing air and are connected to the nasal passages.

210) The functional unit of the lungs where gas exchange occurs is the A) alveolus. B) bronchiole. C) sinus. D) glottis. E) trachea.

210) A The pharynx, trachea, bronchioles, etc., are passageways for the incoming and outgoing air. No exchange of gases occurs in these tubes. Oxygen and carbon dioxide move across the membranes lining the alveoli.

211) Increasing the size of the thoracic cavity through contraction of the diaphragm and rib muscles causes A) an inhalation. B) an exhalation. C) coughing. D) positive pressure in the lungs. E) swallowing.

211) A Inhalation is an active process. The diaphragm and rib muscles contract and the thoracic cavity enlarges drawing air into the lungs.

212) The nephron of mammals and Malpighian tubules of insects are both involved in water and salt balance. They are also similar in that they are both A) involved in elimination of nitrogenous wastes. B) involved in the elimination of digestive wastes. C) attached to the digestive system. D) attached to the respiratory system. E) found in the kidneys.

212) A Malpighian tubules are involved in eliminating nitrogenous wastes, similar to nephrons in the kidneys of mammals. Unlike the kidneys of mammals, the Malpighian tubules of insects are attached to the digestive tract of the insect.

213) Which event occurs during inspiration but not expiration? A) The rib cage moves out and up. B) The diaphragm relaxes and moves up. C) Pressure in the lungs increases. D) Air is pushed out of the lungs. E) The rib cage moves down and inward.

213) A During inspiration, the rib cage moves up and out. The rest of the events occur during expiration.

214) The best definition of a nutrient is A) any food taken into the body. B) a food component which performs a physiological function in the body. C) a food component which can be stored in the body for future energy needs. D) an essential vitamin or mineral. E) a food component which enhances one's health.

214) B A nutrient is a food component that performs a physiological function in the body. There are nutrients in any food taken into the body, but some foods are better sources of nutrients than others. Nutrients can be classified as macronutrients and micronutrients.

215) Energy needs are supplied by A) carbohydrates, lipids, and proteins. B) micronutrients. C) antioxidants. D) fiber. E) essential amino acids.

215) A The macronutrients—carbohydrates, lipids, and proteins—are the macromolecules that serve as the energy sources for the body.

216) Micronutrients A) supply the body's energy needs. B) are needed in large quantities. C) include lipids and proteins. D) include vitamins and minerals. E) include carbohydrates.

216) D Micronutrients are not needed in large quantities because instead of supplying the body's energy needs, they are needed for metabolic activities. Micronutrients include vitamins and minerals.

217) Nutrients that are deemed to be "essential" are those which A) the body is not able to produce. B) the body is able to produce so no food source is needed. C) are needed in very low quantities. D) are essential for muscle development. E) make up a large proportion of the body.

217) A Certain nutrients, including some amino acids, fatty acids, vitamins, and minerals, must be obtained through the diet because the body cannot synthesize them. These nutrients are termed essential nutrients.

218) Fiber is important in the diet in A) providing glucose for cells. B) stimulating movements of the large intestine. C) assisting in fat digestion in the small intestine. D) aiding absorption of fats in the small intestine. E) providing essential amino acids.

218) B Fiber is an indigestible component of plant foods. It is important for normal movement of food through the large intestine.

219) Trans fats are A) found naturally in all animals. B) found naturally in all plants. C) produced by hydrogenating unsaturated oils. D) produced by hydrogenating saturated fats and unsaturated oils together. E) produced by hydrogenating polysaturated fats.

219) C Fats are classified as being saturated, unsaturated, and trans fats. Trans fats are unsaturated fats, which are modified through a chemical process called hydrogenation of unsaturated fats. Less healthy saturated fats are typically found in animal sources and more healthy unsaturated fats are typically found in plant sources.

220) Proteins must be ingested in order to obtain A) necessary trans fats. B) essential amino acids. C) essential cholesterol. D) needed minerals such as potassium and magnesium. E) needed vitamins such as vitamin C.

220) B Proteins are complex molecules composed of amino acids. Essential amino acids cannot be manufactured by the body and so must be ingested in protein food sources.

221) Which of the following is an inaccurate statement about antioxidant vitamins? A) They include certain water-soluble vitamins, specifically vitamin C. B) They are abundant in fruits and vegetables. C) They protect the body against free radicals. D) They include certain fat-soluble vitamins, specifically vitamins A and E. E) They are difficult to get in the diet.

221) E Antioxidant vitamins A, E, and C help the body fight free radicals, particles which interfere with normal metabolic activities. Antioxidants are abundant in fruits and vegetables and easy to get in a normal diet.

222) If a person increases his food intake without increasing his energy need for metabolic functions or processing, what will he need to do in order to maintain his weight? A) decrease physical activity B) increase physical activity C) consume additional vitamins D) drink additional water E) drink less water

222) B The intake and output of energy must be equal for an individual to maintain his current weight. Food supplies the input of energy. Output includes energy needed for metabolic functions and for the processing of food. If an individual eats more food, he will need to exercise more to offset the increased intake of energy.

223) Which of the following is part of a plan to maintain a healthy weight? A) physical activity B) a kilocalorie output equal to the kilocalorie input C) appropriate intake of vitamins and minerals D) moderate intake of fats E) All of the above are part of a plan to maintain a healthy weight.

223) E For an individual to maintain a healthy weight, he must have an energy intake equal to its output. A moderate intake of fat will help with this energy balance. Appropriate intake of vitamins and minerals will allow the body to use the energy efficiently.

224) If egg yolks are a source of cholesterol, why doesn't eating a few eggs a week raise blood cholesterol? A) Cholesterol from eggs does not affect HDL-cholesterol levels. B) The impact on LDL-cholesterol levels is greater from dietary saturated and trans fats than from cholesterol. C) Cholesterol from eggs naturally lowers LDL-cholesterol levels. D) The human body produces more cholesterol than is in the two eggs. E) Cholesterol from eggs naturally raises LDL-cholesterol levels.

224) B Cholesterol is produced by the human body and it is ingested in foods. There are low-density lipoproteins (which transport cholesterol in the blood) and high-density lipoproteins (which transport it out of the body). As with other foods from animal sources, eggs contain cholesterol. It is safe to consume two eggs a week without raising cholesterol levels because dietary saturated fats and trans fats raise LDL cholesterol levels more than dietary cholesterol.

225) The USDA recommends which type of food should compose the smallest percentage of our diet? A) fruits and vegetables B) fats and oils C) meat, eggs, and nuts D) breads and cereals E) dairy products

225) B Grains, vegetables, and fruits should be a large proportion of the diet. Fats and oils, while important for normal health, should only be consumed in small amounts.

226) When looking at a food label, in order to know how many calories you will ingest, it is important to know total number of calories and A) serving size. B) % daily value of protein. C) number of grams of fat. D) number of grams of fiber. E) % daily value of sodium.

226) A When eating packaged food, it is important to know both the total number of calories and the size of a serving. Without knowing the serving size, it is very easy to consume more than a single serving in a sitting.

227) Lipids A) add to fecal bulk. B) regulate metabolism and physiological development. C) may be used to make certain hormones and vitamin D. D) should be the main component of a healthy diet. E) are found only in low amounts in animal sources of food.

227) C Lipids, which include fats and cholesterol, are used as an energy source and used to store energy long term. Cholesterol is specifically used to make steroid hormones and vitamin D.

228) Carbohydrates A) should not comprise a large amount of the diet. B) are mostly found in animal sources of food. C) are stored as starch by animals. D) are converted to glucose for transport in the blood. E) are stored for insulation and protection of organs.

228) D Carbohydrates are an important component of a normal diet. They are found mostly in plant sources of food and are converted to glucose for transport in the blood.

229) Which food choice below offers the healthiest fat for your heart? A) oily fish B) red meat C) whole milk D) cheese E) shrimp and lobster

229) A Most plant sources of lipids are healthy choices. It is more difficult to find truly healthy animal sources. One of the best sources is fish, both white and coldwater species.

230) Which of the following minerals is incorrectly matched with its source? A) calcium - leafy green vegetables B) phosphorus - meat C) iodine - seafood D) zinc - fruit E) magnesium - whole grains

230) D Good sources of zinc include meats, legumes, and whole grains. Fruits are good sources of certain vitamins such as C and A.

231) Which of the following minerals is incorrectly matched with its function in the body? A) potassium - nerve conduction B) sulfur - component of some amino acids and vitamins C) iron - bone growth D) sodium - water balance E) copper - iron metabolism

231) C Minerals, unlike macronutrients, are not sources of energy for the body but are important for metabolic activities of the body. Iron is an important part of hemoglobin and so is important for the transport of oxygen in the blood.

232) A serving of food contains 9g carbohydrate, 3g protein, and 5g fat. The total calories per serving of this food is A) 73. B) 83. C) 93. D) 103.

232) C Each gram of carbohydrate and protein contains 4 calories. Each gram of fat contains 9 calories.

233) Which of the following foods is considered an empty-calorie food? A) potato chips B) broccoli C) sweet potatoes D) salmon E) whole-grain pasta

233) A Empty-calorie foods are foods that while they contribute calories, do not contribute any significant amount of nutrients, such as vitamins or minerals.

234) Yellow-orange and dark-green fruits and vegetables are a good source of A) vitamin A. B) vitamin D. C) vitamin E. D) biotin. E) vitamin C.

234) A Vitamin A is related to beta carotene. Beta carotene is found in yellow-orange and dark-green fruits and vegetables. As with other vitamins, vitamin A can readily be obtained from a healthy diet.

235) Which of the following is a healthy body mass index? A) 20.3 B) 26.6 C) 29.2 D) 32.8 E) 41.5

235) A Body mass index considers an individual's weight in relation to his or her height. A healthy BMI is between 18.5 and 24.9. Anything over that is considered overweight to obese.

236) Mark is 72 inches tall and weighs 180 pounds. His body mass index is A) 24.4. B) 20.0. C) 29.8. D) 33.2. E) 35.4.

236) A Body mass index considers an individual's weight in relation to his or her height. A healthy BMI is between 18.5 and 24.9. Anything over that is considered overweight to obese. To calculate one's BMI, his weight in pounds is multiplied by 703.1 and then divided by the square of his height in inches.

237) Which of the following substances is incorrectly matched with its caloric value? A) carbohydrate - 4 kcal-gram B) fat - 4 kcal-gram C) water - 0 kcal-gram D) protein - 4 kcal-gram E) fiber - 0 kcal-gram

237) B Water and fiber are not used by the body for energy and have 0 kcal/gram. Proteins and carbohydrates have 4 kcal/gram and fats have 9 kcal/gram.

238) Which statement is correct about empty-calorie foods? A) Empty-calorie foods have a high amount of sugar and-or fat in relation to the vitamin content. B) Empty-calorie foods have a low amount of sugar and-or fat in relation to the vitamin content. C) Empty-calorie foods have a high amount of protein in relation to the vitamin content. D) Empty-calorie foods have a high amount of vitamins in them. E) Empty-calorie foods have a high amount of fiber in them.

238) A Empty-calorie foods have high amounts of fat and/or sugar in relation to their vitamin and mineral content.

239) It is midsummer and Julie was out playing softball all day. She had to leave the game early because she was not feeling well. What is most likely happening to Julie? A) Her body is dehydrated and her core body temperature is increasing. B) Her body is dehydrated and her core body temperature is decreasing. C) Her body is fatigued from all of the exercise. D) Her muscles are cramped up due to a lack of calcium. E) Her aerobic conditioning was not strong enough to handle all of the exercise.

239) A If an individual doesn't maintain adequate hydration levels, he or she can become dehydrated. Dehydration can lead to an increase in the core body temperature, which, if left unchecked, can pose a serious health risk. Warmer weather and physical exercise can both increase the amount of water lost.

240) Which of the following food sources would contain the least amount of fiber? A) chicken B) beans C) peas D) nuts E) fruits

240) A Fiber includes various nondigestible carbohydrates derived from plants. Food sources rich in fiber include beans, peas, nuts, fruits, and vegetables. Whole-grain products are also a good source of fiber and are therefore more nutritious than food products made from refined grains.

241) Which of the following is the least likely to contribute protein to the diet? A) eggs B) fish C) beans D) milk E) apples

241) E Meat, fish, poultry, eggs, nuts, dried beans and peas, soybeans, cereal products, milk, cheese, and yogurt are all good sources of protein in the diet.

242) Which of the following pieces of nutritional information is not included on the nutritional label of a food package? A) daily % of water available in the food B) daily % of protein available in the food C) daily % of fat available in the food D) serving size E) calories based upon serving size

242) A Food labels do not list the % of water available in the particular food product.

243) Which of the following is a function of the digestive system? A) eliminate dead bacteria B) eliminate nondigestible food C) eliminate bile pigments from the breakdown of hemoglobin D) absorb nutrients E) All of the above are functions of the digestive system.

243) E The primary function of the digestive system is the intake and processing of food so that nutrients can be absorbed into the body. Additional functions include the elimination of nondigestible food, dead bacteria, and bile pigments.

244) Humans are omnivores as shown by the type of A) enzymes secreted in human saliva. B) urine produced by humans. C) human teeth. D) human taste buds. E) enzymes secreted in human intestines.

244) C One of the adaptations of mammals to their diet is their teeth. The incisors, canines, premolars, and molars change in number and shape depending on the importance of plant matter and animal matter in their diets.

245) Starch digestion begins in the _____ and protein digestion begins in the _____. A) mouth; small intestine B) stomach; small intestine C) mouth; stomach D) stomach; large intestine E) small intestine; stomach

245) C Starch digestion begins with amylase in the mouth; protein digestion begins with pepsin in the stomach. Both processes are completed in the small intestine.

246) Food in the digestive tract is called chyme after A) the tongue mixes it with saliva. B) the stomach processes it. C) all nutrients have been absorbed by the small intestines. D) elimination through the anus. E) it is chewed by the teeth.

246) B After food is chewed and mixed with saliva in the mouth, it forms a soft lump called a bolus. When the bolus passes into the stomach and is mixed with its secretions, it becomes a liquid called chyme. After processing by the small intestine and large intestine, the contents of the digestive tract are now feces and will be eliminated from the body.

247) Which of the following is in the correct order for protein digestion? A) pepsin - peptides - peptidase - amino acids B) peptidase - peptides - pepsin - amino acids C) peptidase - amino acids - pepsin - peptides D) amino acids - peptidase - peptides - pepsin E) peptides - pepsin - peptidase - amino acids

247) A Pepsin breaks down proteins into the smaller-chained peptides in the stomach. Protein digestion continues in the small intestine through the action of peptidases which digest the peptides into amino acids.

248) Which of the following is a function of the small intestine? A) storage of indigestible material B) absorption of water C) absorption of salts D) absorption of vitamin K E) absorption of amino acids

248) E The large intestine is the final portion of the digestive tract. The last amounts of water and salts are absorbed along with vitamins, such as vitamin K, produced by bacteria housed in the large intestine. Indigestible materials are stored and used to make feces which are eventually eliminated. Most nutrients are absorbed in the small intestine.

249) Which of the following is a function of the pancreas? A) produces plasma proteins such as fibrin and fibrinogen B) detoxifies the blood by removing poisonous substances C) produces insulin and glucagon D) produces bile E) produces urea from amino acids

249) C The liver, an accessory organ of the digestive tract, has multiple functions which include detoxification of the blood, and production of plasma proteins, urea, and bile. It is also involved in the maintenance of blood glucose levels by responding to hormones such as glucagon and insulin which are produced by the pancreas.

250) Which of the following incorrectly pairs the enzyme and the molecule on which it acts? A) salivary amylase - starch B) pepsin - protein C) maltase - starch D) trypsin - protein E) pancreatic amylase - starch

250) C Foods molecules are digested in stages by enzymes in the digestive tract. Amylases are involved in the digestion of starches. Trypsin and pepsin both digest proteins. Maltase digests maltose into glucose and peptidases finish the protein digestion into amino acids.

251) The digestion and absorption of fats differs from that of sugars and proteins in that A) sugars and proteins must be emulsified before being digested. B) fats are absorbed into lymphatic capillaries instead of blood capillaries. C) sugars and proteins interact with bile salts in order for absorption to occur. D) fats are digested primarily in the stomach. E) fats do not require digestion before being absorbed.

251) B All nutrients must be digested by enzymes into their simplest components before being absorbed. Fats must be emulsified by bile salts so that the enzymes may act upon them. Once digested, simple sugars and amino acids are absorbed into the blood capillaries and fats are absorbed into the lymph capillaries.

252) Alicia and Juan are hiking in the woods and come across the skull of an animal. The teeth are still in the skull. The front teeth, or incisors, are short but sharp. The canines are long and pointed. The back teeth, or molars and premolars, are jagged. Based on these teeth, the skull likely belonged to a(n) A) carnivore. B) omnivore. C) herbivore. D) human. E) There is not enough information to answer.

252) A In mammals, the teeth are divided into four types: incisors, canines, premolars, and molars. Omnivores, herbivores, and carnivores have different forms and numbers of these teeth. Carnivores' incisors are short but sharp for scraping meat off bones. Their canines are enlarged for killing their prey. The premolars and molars are jagged for tearing apart flesh. Herbivores have sharp incisors for clipping vegetation and large, flat premolars and molars for grinding food. Omnivores have teeth that are less differentiated and a combination of the types seen in herbivores and carnivores.

253) An unfertilized egg from a female Komodo dragon may develop directly into a young Komodo dragon. This is an example of A) parturition. B) assisted reproduction. C) parthenogenesis. D) abiogenesis. E) copulation.

253) C Parthenogenesis is a modified form of sexual reproduction in which an egg can develop without being fertilized.

254) The male gonad is the _____, and the female gonad is the _____. A) ovary; testis B) vagina; penis C) testis; uterus D) testis; ovary E) penis; vagina

254) D Males have testes, and females have ovaries.

255) Animals with both male and female reproductive systems are A) hermaphroditic. B) chimeric. C) parthenogenetic. D) asexual. E) menopausal.

255) A Hermaphroditic animals include earthworms; they have both male and female gonads.

256) Which of these is viviparous? A) salmon B) parrot C) bullfrog D) crayfish E) moose

256) E A moose gives birth to live young, and is thus viviparous.

257) Which one adaptation was most important in enabling animals to reproduce on land? A) penis B) shelled egg with extraembryonic membranes C) placenta D) gametes E) copulation

257) B The shelled egg with its extraembryonic membranes was key in allowing embryos to develop out of the water.

258) Which of these correctly traces the path of a sperm from its origin to the point at which it leaves the male reproductive tract? A) testis→epididymis→vas deferens→ejaculatory duct→urethra B) epididymis→vas deferens→testis→urethra→ejaculatory duct C) testis→epididymis→vas deferens→urethra→ejaculatory duct D) vas deferens→epididymis→testis→ejaculatory duct→urethra E) testis→vas deferens→epididymis→ejaculatory duct→urethra

258) A Sperm pass from the testis to the epididymis, and from there to the vas deferens. During arousal, sperm enter the ejaculatory duct and then the urethra.

259) Which part of male anatomy is part of both the urinary system and the reproductive system? A) testis B) seminal vesicle C) urethra D) prostate gland E) bulbourethral gland

259) C The urethra in males is a part of both the urinary system and the reproductive system.

260) Sperm are produced A) by Sertoli cells. B) in the epididymis. C) by interstitial cells. D) in the seminiferous tubules. E) in the seminal vesicles.

260) D Sperm are produced in the seminiferous tubules of the testes.

261) Which of these serves as the female organ of copulation and the birth canal? A) uterus B) oviduct C) ovary D) vagina E) urethra

261) D The vagina receives the penis during sexual intercourse and serves as the passageway for the fetus during childbirth.

262) Which lists the structures a secondary oocyte must pass through on its way out of a woman's reproductive tract? A) oviduct, uterus, vagina B) vagina, oviduct, uterus C) vagina, uterus, oviduct D) uterus, oviduct, vagina E) oviduct, vagina, uterus

262) A When a secondary oocyte is released from the ovary at ovulation, it is swept into an oviduct. It then passes down the oviduct to the uterus. If a pregnancy does not occur, the oocyte leaves the uterus by way of the vagina as part of the menses.

263) Which of these is mismatched? A) ovulation - luteinizing hormone (LH) peaks B) menstruation - follicle-stimulating hormone (FSH) peaks C) secretory phase - progesterone peaks D) menstruation - progesterone declines E) proliferative phase - estrogen levels rise

263) B FSH peaks at the time of ovulation, as does LH.

264) Which of these places the events of the menstrual cycle in the correct order? A) menstrual phase→secretory phase→proliferative phase→ovulation B) menstrual phase→ovulation→secretory phase→proliferative phase C) menstrual phase→proliferative phase→ovulation→secretory phase D) menstrual phase→proliferative phase→secretory phase→ovulation E) menstrual phase→ovulation→proliferative phase→secretory phase

264) C The 28-day menstrual cycle begins with menstruation. During the proliferative phase, the endometrium grows progressively thicker. Ovulation occurs on day 14 of the ovarian cycle, which coincides with the midpoint of the menstrual cycle. From day 14 on, the endometrium becomes vascular and glandular during the proliferative phase. If pregnancy does not occur, then the cycle begins again with menstruation, and the inner layer of the endometrium is shed.

265) Which of the following structures is part of the reproductive system? A) oviduct B) ovary C) cervix D) vagina E) All of the answers are parts of the female reproductive system.

265) E All of the answers listed are parts of the female reproductive system.

266) Which organism is most likely to reproduce by fragmentation? A) hydra B) sponge C) bird D) honeybee E) frog

266) B Fragmentation is an asexual type of reproduction in which an organism is cut into pieces and the pieces each develop into a new individual. This type of reproduction occurs in sponges and corals, as well as with many flatworms and echinoderms.

267) If you could mark the ectoderm of a mouse embryo so that all tissues and organs descended from ectoderm were easily identifiable, where would you expect to find the marker? A) skeletal muscles and dermis B) cardiovascular and reproductive systems C) nervous system and epidermis D) lining of the digestive and respiratory tracts E) urinary bladder and its lining

267) C The ectoderm gives rise to the nervous system and epidermis, plus the epithelial linings of the oral cavity and rectum.

268) Whatis the extraembryonic membrane that serves as the first site of blood cell formation for the embryo? A) chorion B) allantois C) amnion D) yolk sac E) zona pellucida

268) D The yolk sac is the first site of blood cell formation.

269) The failure of a couple to achieve pregnancy after a year of regular, unprotected intercourse is termed A) parthenogenesis. B) menopause. C) contraception. D) infertility. E) abortion.

269) D Infertility is when a couple cannot become pregnant after trying regularly for a year.

270) Which of these is part of the female reproductive system? A) oviduct B) uterus C) vagina D) ovary E) All of the answers are parts of the female reproductive system.

270) E All of the answers are parts of the female reproductive system.

271) Secondary sex characteristics in males develop due to the influence of A) follicle-stimulating hormone (FSH). B) progesterone. C) human chorionic gonadotropin (hCG). D) estrogen. E) testosterone.

271) E Male secondary sex characteristics (such as facial hair, masculine body proportions, deep voice, etc.) develop due to testosterone.

272) How does follicle-stimulating hormone (FSH) affect the male reproductive system? A) promotes testosterone production B) causes erection C) promotes spermatogenesis D) stimulates ovulation E) triggers ejaculation

272) C In males, FSH promotes spermatogenesis.

273) In European countries such as Italy, people are delaying childbirth and or choosing to have no children or only one child. Which of the following age structure diagrams illustrates this type of trend? A) increasing population B) decreasing population C) stable population D) This trend is not depicted in these diagrams.

273) B In these countries, there are fewer individuals in the prereproductive age group.

274) Which of the following is true about the majority of less-developed countries (LDCs)? A) They consume the most fossil fuels. B) They support the highest populations. C) They produce the most hazardous wastes. D) They have the largest environmental impact. E) They exhibit thehighest per capita resource consumption.

274) B Overpopulation is more common in LDCs, but typically per capita resource consumption is higher in MDCs.

275) Which of the following represents replacement reproduction? A) A couple has only one child. B) A couple has no children but each has two siblings. C) Each couple has only two children. D) A government policy limits the number of children per family. E) A couple has four children.

275) C Replacement reproduction occurs when each couple in a population only has two children.

276) Prairie dogs are highly social, burrow-dwelling rodents. Families have a strict social hierarchy and their "towns" can span hundreds of acres. In one colony, 750 animals live in a 500 m 2 area. What is the population density? A) 15 B) 1.5 C) 150 D) 2.5 E) 25

276) B Population density is determined by dividing the number of animals by the area that they occupy.

277) What is meant by an organism's biotic potential? A) The rate at which the population grows. B) The number of offspring that an organism produces over its entire life span. C) The age at which an organism reaches sexual maturity. D) The number of individuals in the prereproductive stage. E) The maximum rate of population growth with unlimited resources.

277) E The biotic potential determines how quickly a population can grow under ideal circumstances.

278) All of the following impact a population's ability to reach biotic potential except A) resource abundance. B) the number of offspring produced each reproductive cycle. C) chances of survivorship until sexual maturity. D) how frequently each individual in the population reproduces. E) the age at which reproduction ends.

278) E The age at which reproduction begins is more important in determining the biotic potential.

279) Exponential growth A) has threephases. B) results in accelerating growth. C) produces an S-shaped growth curve. D) requires limited resources. E) declines over time.

279) B Exponential growth produces a J-shaped curved due to accelerated growth over time.

280) All of the following are true of BOTH logistic growth and exponential growth except A) they both have a lag phase. B) they both have an exponential growth phase. C) they both have a stable equilibrium phase. D) they are both a type of population growth. E) they are influenced by resource availability.

280) C Logistic growth reaches a carrying capacity due to the limited number of resources.

281) Based upon the features listed, which of the following species is the most likely to go extinct? A) Species A has a small population, has a narrow habitat tolerance, and lives on an island. B) Species B has a large population, can withstand a large spectrum of environmental conditions, and lives all over the United States. C) Species C has a small population, can withstand a large spectrum of environmental conditions, and lives within a small section of the forest. D) Species D has a moderate population, can withstand a moderate spectrum of environmental conditions, and lives on an island. E) Species E has a large local population, broad tolerance to environmental change, and a large geographic range.

281) A Three factors help determine if a species is likely to go extinct or not: the size of the geographic range, degree of habitat tolerance, and size of local populations. If the geographic range is small, the population is small, and the species cannot tolerate environmental change, it has the highest risk of going extinct.

282) Which field of biology studies all aspects of biodiversity? A) conservation biology B) histology C) geology D) entomology E) environmental science

282) A Conservation biology is a discipline of ecology that studies all aspects of biodiversity, with the goal of conserving natural resources, including wildlife, for the benefit of this generation and future generations.

283) What is the correct ratio of fossil fuel consumption between the MDCs and LDCs? A) MDCs 60% vs. LDCs 40% B) MDCs 40% vs. LDCs 60% C) MDCs 22% vs. LDCs 78% D) MDCs 50% vs. LDCs 50% E) MDCs 80% vs. LDCs 20%

283) A MDCs consume approximately 60% of the world's fossil fuels, while the LDCs consume approximately 40%.

284) Which of the following statements is correct about the comparison between MDCs and LDCs? A) MDCs consume 4 timesas many metals and 3 times as much paperas LDCs. B) MDCs consume twice as much paper and 4 times as many metals as LDCs. C) The population of MDCsis growing twice as fast as the population of LDCs. D) MDCs produce 10 timesas much hazardous waste and consume 3 times as much paper as LDCs. E) MDCs consume 3 times as many metals and 4 times as much paperas LDCs.

284) A MDCs make up 22% of the population and LDCs make up 78%. MDCs produce 90% of the hazardous wastes and LDCs produce 10%. MDCs consume 60% of the fossil fuels and LDCs consume 40%. MDCs consume 80% of the metals and LDCs consume 20%. MDCs consume 75% of the paper and LDCs consume 25%.

285) Which statement about ecology and environmental science is correct? A) Ecology is a fieldof science that helps negate the information that is derived from the field ofenvironmental science. B) During the study of ecology, only living organisms are studied, while the nonliving aspects are studied within the field of environmental science. C) During the study of environmental science, living organisms are studied, while the nonliving aspects are studied within the field of ecology. D) The field of environmental science applies the ecological principles to human-based concerns. E) The field of ecology focuses on human-based issues and uses them to help determine if there is going to be an environmental change.

285) D The field of environmental science applies ecological principles to practical human concerns.

286) During a recent hurricane, 25 individuals of the same butterfly species were blown onto a barrier island in southern Florida. Prior to this event, this species did not inhabit the island, but with the ample vegetation on the island and a lack of predators, the displaced individuals were able to survive and reproduce. After several years, the population stabilized with approximately 150 individuals. The 150 individuals on the island is an example of the A) density-dependent factors. B) biotic potential. C) exponential growth. D) logistic growth. E) carrying capacity.

286) E The maximum number of individuals that an environment can sustain is the carrying capacity. This is where the population growth rate stabilizes.

287) During a recent hurricane, 25 individuals of the same butterfly species were blown onto a barrier island in southern Florida. After several years, the population stabilized with approximately 150 individuals. The butterflies and the flowers that they require for food would be considered an example of a(n) A) organism. B) population. C) community. D) ecosystem. E) biosphere.

287) C Two different populations living in the same region is a community.

288) During a recent hurricane, 25 individuals of the same butterfly species were blown onto a barrier island in southern Florida. In general, each female butterfly lays more than 50 eggs each year, but only a few individuals survive for more than a month after hatching from the eggs. What type of survivorship curve most accurately represents this species? A) type I B) type II C) type III D) type IV E) type V

288) C Organisms that produce lots of offspring that have a high rate of mortality early in life is typical of a type III survivorship curve.

289) During a recent hurricane, 25 individuals of the same butterfly species were blown onto a barrier island in southern Florida. When the butterflies first arrived on the island, they did not have to compete for access to food or space. In addition, there were few natural predators such as wasps and birds which were common on the mainland. As a result, the island population will have a _____ biotic potential compared to the mainland population. A) higher B) lower C) similar D) reduced E) stable

289) A When comparing the same species, biotic potential will be higher for the population with abundant resources and lack of competition.

290) Meghan is studying interactions between caribou and their wolf predators. This is an example of _____ ecology. A) population B) community C) ecosystem D) biosphere E) demographic

290) B This study includes two different populations, which is a community.

291) Which of the following is a characteristic of equilibrium species? A) short life span B) short time to reach sexual maturity C) production of many offspring D) little or no parental care E) logistic growth

291) E Equilibrium species exhibit logistic population growth, with the population size remaining close to or at the carrying capacity.

292) Jacob is studying a population of wrens in Michigan. During one severe winter, 5% of the birds died due to starvation and cold temperatures. Severe weather is an example of A) a density-independent factor. B) a negative growth rate. C) a density-dependent factor. D) an opportunistic population. E) logistic growth.

292) A Abiotic factors such as weather are examples of density-independent factors.

293) Jacob is studying a population of wrens in Michigan. Over several years, he notices that the population always stabilizes at around 45 individuals. Forty-five individuals is A) the density. B) the growth rate. C) a density-dependent factor. D) a density-independent factor. E) the carrying capacity.

293) E The maximum number of individuals that an environment can sustain is the carrying capacity.

294) Which of the following is an example of exponential growth? A) 2,000→2,000→2,000 B) 1,500→1,600→1,700 C) 1,500→1,550→2,010 D) 1,000→1,500→2,000 E) 2,000→1,500→1,000

294) C The population must show accelerating growth. The growth lags at first and then accelerates.

295) Which of the following populations has the greatest biotic potential? A) Population A in which females start to reproduce at 1 year and produce 2 offspring each year. B) Population B in which females reach sexual maturity in 6 months and produce 1 offspring each 12-monthreproductive cycle. C) Population C in which males reach sexual maturity in just 3 months. D) Population D in which individuals reach sexual maturity in 6 months and produce 5 offspring each year. E) Population E in which individuals produce 5 offspring starting at 5 years of age.

295) D Biotic potential is a measure of how quickly a population increases. Thus the more offspring that are produced, the faster the population grows.

296) A community is A) populations of multiple species interacting with one another in a specific area. B) populations of organisms and the abiotic factors in their environment. C) competition for food between individuals in a population. D) all the biotic and abiotic factors in an environment. E) multiple organisms of the same species living in a specific area.

296) A A community is a group of populations of multiple species, interacting with one another within a single environment.

297) An ecosystem A) includes only the plants within a particular area. B) includes all the living organisms within a specific area, but not the abiotic factors. C) includes bothliving and abiotic factors within a particular region. D) always includes equal numbers of plant and animal species. E) only refers to biotic factors in a region.

297) C Ecosystems include both biotic and abiotic factors in a particular region.

298) Which of the following is an inaccurate statement about species diversity? A) It includes species richness. B) It includes species age distribution. C) It is influenced by the relative abundance of species. D) It is influenced by the distribution of the different species. E) It is not impacted by species richness.

298) E The diversity must take into consideration both the number of different species (species richness) and the distribution of these species.

299) Which of the following communities is the least diverse? A) 15 lions, 100 zebras, 80 giraffes B) 50 squirrels, 75 oak trees, 60 maple trees C) 4 crab spiders, 76 goldenrod, 60 echinacea D) 40 bass, 60 minnow, 55 blue gill E) 5 elm trees, 7 beech trees, 6 birch trees

299) C Diversity includes both species richness and species evenness. All 5 have the same number of species (richness), but C has very uneven distribution of species with only 4 spiders.

300) Ecological succession is A) a change in communities caused by human activities. B) a stable community that forms after a change. C) an orderly process of change in the community of organisms. D) what happens to a cultivated field every year that crops are planted. E) competition between opportunistic and equilibrium species.

300) C Community species composition and diversity change over time in a relatively orderly manner.

301) Which of the following is an inaccurate statement about primary and secondary succession? A) both lead to a stable climax community. B) both include a progression of changes in the community over time. C) both occur in regions where soil is already present. D) for both communities, fungi and vascular seedless plants are typically the first species to colonize the area. E) both are colonized first by opportunistic species.

301) C Primary succession occurs where soil is not yet present, while secondary succession occurs where soil is present.

302) Which of the following is an example of an animal's habitiat? A) a small bird living in the dense shrubs at the base of a tree B) two male lizards fighting over access to a female C) a grasshopper feeding on leaves D) an oystercatcher eating bivalves E) lions and hyenas fighting over access to a zebra carcass

302) A This describes the bird's habitat. All the other answers describe a niche which is the animal's role within the environment.

303) The physical space that an organism occupies in its environment is its A) habitat. B) niche. C) bioticfactor. D) role. E) abioticfactor.

303) A Habit refers to the actual spatial position of an organism in its environment.

304) An organism that obtains its food from the process of photosynthesis is a(n) A) autotroph. B) consumer. C) heterotroph. D) decomposer. E) omnivore.

304) A Autotrophs use inorganic nutrients such as carbon dioxide to produce food in the form of glucose.

305) Martin is studying blue gill fish, which are insectivores. How would you classify this fish? A) autotroph and consumer B) autotroph and producer C) heterotroph and decomposer D) autotroph and detritivore E) heterotroph and consumer

305) E Blue gills are carnivores and so are heterotrophs and consumers.

306) If there is 2,000 kg of plant material, how much of this biomass will be converted into top carnivore tissue? A) 20,000 kg B) 2,000 kg C) 200 kg D) 20 kg E) 2 kg

306) E Only 10% of the biomass is transferred from one level to the next. Thus, 200 kg will be transferred to the herbivore level, 20 kg to the carnivore level, and 2 kg to the top carnivore level.

307) The greenhouse effect A) will lead to decreased sea levels. B) decreases the amount of carbon dioxide in the air. C) increases the amount of carbon dioxide in the air. D) is caused by gases such as carbon dioxide trapping heat in the Earth's atmosphere. E) is due to gases forming a barrier around the Earth and insulating the Earth from the sun's rays.

307) D As carbon dioxide and other gases continue to increase in the atmosphere, these gases absorb and reradiate heat back to the Earth leading to a rise in overall temperature across the Earth.

308) The most exclusive level of biological organization that is listed below is A) ecosystems. B) biomes. C) thebiosphere. D) communities. E) populations.

308) E Populations only contain one type of species and therefore are the most exclusive level of biological organization listed. The biosphere which encompasses all ecosystems and thus all spheres where living organisms are found is the most inclusive level listed.

309) Which of the following terrestrial ecosystems is a very cold northern coniferous forest? A) taiga B) tropical rainforest C) temperate rainforest D) prairie E) tundra

309) A Tropical rainforests have high rates of rainfall and warm temperatures. The result is an abundance of aboveground vegetation and higher primary productivity.

310) In aquatic ecosystems, primary productivity is most dependent on A) organic nutrients. B) species richness and diversity. C) the type of soil. D) the rate of photosynthesis. E) inorganic nutrients.

310) E Inorganic nutrients are often limiting factors for growth. Estuaries and marshes have many decomposers which convert organic nutrients to inorganic compounds, which are needed for growth.

311) Which ecosystem makes up approximately 70% of the Earth's surface? A) aquatic; marine B) aquatic; fresh water C) aquatic; coral reefs D) terrestrial; tundra E) terrestrial; rainforest

311) A Aquatic ecosystems are divided into those composed of fresh water and those composed of salt water (marine ecosystems). The ocean, a marine ecosystem, covers 70% of the Earth's surface. Two types of freshwater ecosystems are those with standing water, such as lakes and ponds, and those with running water, such as rivers and streams.

312) As humans continue to use fossil fuels as a primary source of energy, the amount of carbon entering the atmosphere from fossil fuel combustion will continue to increase dramatically. What is the effect of large-scale deforestation on the carbon in the atmosphere? A) Because trees are a major sink for atmospheric carbon, fewer trees will result in less carbon being removed from the atmosphere for photosynthesis. B) As trees are removed, there is more room for carbon to enter the soil directly and be used by other plants. C) The large-scale removal of forests does not have any real effect on atmospheric carbon, because carbon dioxide is not stored in trees. D) Because trees produce carbon dioxide, the amount of carbon in the atmosphere will decrease with their wide-scale removal.

312) A Plants remove carbon dioxide from the atmosphere in order to conduct photosynthesis. As forests are removed, this sink, or storage area, for carbon is taken away, resulting in less carbon dioxide being removed from the atmosphere.

313) How does climate change effect Earth's oceans? A) The pH level of the ocean willshift to a more acidic environment, leading to stress and thepossible extinction of many species of shellfish and corals. B) The pH level of the ocean willshift to a more basic alkaline environment, leading to a decrease in overall productivity. C) As levels of carbon in the atmosphere increase, the amount of carbon in the ocean decreases proportionately. D) Excess carbon in the atmosphere is absorbed by the ocean, which directly increases ocean temperature.

313) A As the CO 2levels in the atmosphere increase, so do the levels in theocean, leading to ocean acidification.

314) Which of the following correctly lists the progression of species present during primary or secondary succession? A) fungi, nonvascular plants, gymnosperms, animals B) nonvascular plants, angiosperm, gymnosperms, fungi C) animals, fungi, nonvascular plants, angiosperms D) angiosperms, nonvascular plants, animals, gymnosperms E) gymnosperms, angiosperms, fungi, nonvascular plants

314) A With both primary and secondary succession, there is a similar progression of species starting with fungi, nonvascular plants, then gymnosperms/angiosperms and animals.

315) Which of the following is a nonrenewable resource? A) fossil fuels B) food crops C) water D) wild game E) solar energy

315) A Most scientists would consider fossil fuels to be a nonrenewable resource because it takes many millions of years to produce them, far more slowly than they are being used.

316) Pollution is defined as A) an alteration in land usage. B) an undesirable alteration to the environment. C) the impact of human activity on the environment. D) the impact of animal and plant species on the environment. E) the introduction of a new species into an environment.

316) B While the impact of many species, especially humans, may alter an environment, pollution is defined as any undesirable alteration to the environment.

317) Which of the following activities contribute to beach erosion? A) construction of groynes B) filling coastal wetlands C) use of seawalls to protect cities from hurricane storm surges D) rising sea levels E) All of the above describe activities that contribute to beach erosion.

317) E All of the answers describe activities that contribute to beach erosion.

318) Desertification is primarily caused by which of the following activities? A) overgrazing of livestock B) overplanting of crops C) overuse of farm machinery D) lack of rainfall E) restoration of wetlands

318) A Overgrazing by livestock removes many of the plants that help hold in the soil; the soil that remains is unable to hold water so that plants can grow, and the land becomes barren and dry. As the remaining vegetation is removed to feed the animals and human populations, the process accelerates, to the point where the land is no longer arable.

319) Desertification and deforestation are similar in that both involve A) overpopulation of an area by humans. B) loss of plant and animal life in an area. C) lack of rainfall in an area. D) overgrowth of undesirable plants in an area. E) loss of wetland habitats.

319) B Both desertification and deforestation are caused by the removal of plants from an area. Land is often deforested for agricultural use, but is too often subjected to desertification once the land becomes infertile.

320) Which of the following is a major drawback of dams? A) saltwater intrusion B) providing irrigation water C) sediment buildup D) depletion of aquifers E) deforestation of nearby lands

320) C Of these choices, only sediment buildup is a problem that is contributed to by damming streams and rivers, although there are many other problems that can be created by dams. Sediment buildup can reduce the storage capacity of reservoirs.

321) Extensive irrigation may contribute to desertification because A) the water dissolves soil nutrients, making them unavailable to plants. B) water used in irrigation leaves behind toxic substances in the soil. C) runoff of water leaves silt deposits behind, which reduce the ability of plants to grow. D) a reduction of water available in the aquifer lowers lake, river, and stream levels. E) evaporation of water used in irrigation causes salinization of the land, reducing the ability of plants to grow.

321) E While extensive use of water from aquifers does create major problems, it is evaporation of water used in irrigation that can leave behind excess salts and minerals, which over time can reduce the fertility of the land. The use of drip irrigation systems, which reduce water usage, and only irrigating at night when less of the water evaporates can over time reduce costs, protect the fertility of the land, and conserve valuable water resources.

322) In which ways does overfishing lead to decreased biodiversity? A) It reduces the available habitat for other species. B) Overfishing allows fished species to overpopulate once the larger individuals are removed from the population, which in turn depletes the species' food sources. C) Newer technologies allow the fishing fleet to take a larger catch while leaving larger numbers of breeding pairs, which overpopulate and degrade the environment. D) It depletes fish that feed on some species and serve as food sources for other species, leading to the eradication of some species and the overpopulation of others. E) It depletes food sources for aquatic mammals, which then overpopulate.

322) D By removing large numbers of a fish species, the food web is disrupted, leading to the overpopulation of organisms the fish species preyed on, and the depletion of species that were dependent upon the fish species as a food source. This cycle repeats as other species are depleted or overpopulated, leading to a reduction in species diversity in the environment. Most modern fishing techniques increase catch but also trap other unwanted species, which are discarded, further disrupting the food web. Furthermore, these techniques are not selective in the individuals of the fish species that are caught—smaller individuals are as likely to be caught as are those of reproductive age.

323) Hydropower and wind power are similar in that both are A) nonrenewable energy sources. B) renewable energy sources. C) commonly used worldwide as power sources. D) dependent in part on fossil fuels. E) sources of environmental pollution.

323) B Both hydropower and wind power are renewable energy sources. Hydropower is commonly used in some countries, but neither hydropower nor wind power provides the majority of energy used worldwide.

324) Before solar energy can become usable for consumers, which of the following events must occur? A) Energy must be collected, converted into another form, and stored until needed. B) Energy must be converted into another form, stored until needed, and then converted into heat. C) Energy must be used to heat water, and solar energy is combined with steam to heat a photovoltaic system that produces electricity. D) Solar energy passes through a photovoltaic cell, which then stores the energy as heat until it is needed. E) Solar energy is used to power a photovoltaic cell, which splits water into hydrogen and oxygen, and the hydrogen can be used to provide energy.

324) A Solar energy is diffuse energy that must be (1) collected, (2) converted to another form, and (3) stored if it is to compete with other available forms of energy.

325) Mercury can enter an aquatic food chain and collect in fish as well as people who eat fish. This is an example of which of the following processes? A) biotic potential B) biological magnification C) salinization D) bioremediation E) biological accumulation

325) B Biological magnification refers to the process by which contaminants taken up by living organisms may become more concentrated as they are passed up the food chain. Biological magnification is one of the many reasons that even low levels of many pollutants pose a threat to the ecosystem and to human populations as well.

326) Which of the following types of compounds have been implicated in ozone depletion? A) chlorofluorocarbons (CFCs) B) volatile organic compounds (VOCs) C) DDT D) polychlorinated biphenyls (PCBs) E) chromium

326) A CFCs have been implicated in the thinning of Earth's ozone layer, and have been banned in most MDCs in response. It is expected that the ozone layer will not recover fully until nearly 2050.

327) How do forests regulate global climate? A) Forests replenish atmospheric oxygen. B) Forests provide shade. C) Forests block wind. D) Forests add moisture to the atmosphere via transpiration. E) Forests take up carbon dioxide.

327) E Globally, forests regulate the climate, because they take up carbon dioxide, a greenhouse gas. When the leaves of trees photosynthesize, they use carbon dioxide, which is stored as the wood of the tree.

328) Which of the following groups is suspected of causing climate change? A) fossil fuel usage, deforestation, and agriculture B) overfishing and hydropower usage C) fossil fuel usage and overfishing D) salinization and desertification E) erosion, deforestation, pollution, and salinization

328) A Greenhouse gases, naturally present in the atmosphere, allow solar energy to reach Earth's surface. At night, much of this solar energy is re-emitted by the Earth as infrared heat, but some of it is absorbed by greenhouse gases and re-emitted back to the surface of the Earth, causing warming. Deforestation has the effect of removing sources of CO 2 storage, as fewer trees will result in less carbon being stored and used by plants. Agriculture has much of the same effect, in addition to being a source of methane, another greenhouse gas.

329) The major cause of the loss in Earth's biodiversity is A) fossil fuel usage. B) pollution. C) habitat loss. D) overfishing and water pollution. E) agricultural runoff.

329) C While pollution, fossil fuel usage, overfishing, and agriculture negatively impact many species, studies have indicated that habitat loss is the greatest threat to biodiversity. Habitat loss may be caused by any number of human activities.

330) Which of the following is a benefit of biodiversity? A) development of novel medicines B) waste disposal C) new and better crop plants D) climate regulation E) All of the choices are benefits of biodivesity.

330) E All of the choices are benefits of biodiversity.

331) Forests and other natural ecosystems, such as wetlands, exhibit the "sponge effect," meaning that they A) soak up water from runoff and rainfall, and thus accumulate pollutants. B) soak up water from runoff and rainfall, releasing it at a regular rate that moderates flooding of streams and rivers. C) soak up pollutants from runoff and rainfall, releasing it quickly into streams and rivers and raising their levels. D) draw water away from rivers and streams, lowering their levels. E) soak up water from runoff and rainfall, saturating nearby ecosystems.

331) B The "sponge effect" refers to the ability of forests (and wetlands) to soak up water and release it slowly to other ecosystems. This partially explains why flooding becomes prevalent along rivers and streams where deforestation and wetland destruction have occurred. In the United States, efforts are currently being made to restore forests and wetlands along many major rivers to alleviate flooding problems caused by dams and levees.

332) Human society in its current form is unsustainable because A) important natural resources are being consumed more quickly than they can be replenished. B) renewable energy sources require too many land and this is reducing the area available for farming. C) recycling has eliminated the need for the mining of some mineral resources. D) freshwater is being effectively preserved through conservation. E) diverting agricultural yield for feeding livestock supplies enoughprotein to fulfill community's dietary needs.

332) A While some of the statements are true, such as the fact that conservation can preserve freshwater supplies, the only statement that explains why our current society is unsustainable is that natural resources are being consumed at an alarmingly high rate, far more quickly than they can be replenished.

333) Which of the following is inconsistent with the idea of making urban environments more sustainable? A) development of more energy-efficient means of transportation B) utilization of "green roofs" C) creation of "greenbelts" D) development of new sections in cities as older ones become dilapidated and unusable E) use of native species in landscaping that require less maintenance and attract bees and butterflies

333) D Redevelopment of older sections of cities lessens the need for destruction of land for development and protects the natural environment.

334) The Canada lynx ( Lynx canadensis) is currently listed as an endangered species. Which of the following would play the greatest role in removing the lynx from the endangered species list? A) create a law that bans the development and use of roads for snowmobiling and skiing in the lynx habitat B) pass a law that restricts hunting of lynx C) increase the amount of available prey for the lynx D) establish limits on the amount of timber that can be harvested from the forests that the lynx use as their habitat E) remove any potential competitors (i.e., wolves and coyotes) from the lynx habitat to increase the amount of resources available for the lynx

334) A The main reason for the endangered status of the lynx is the loss of habitat due to snowmobiling and skiing. While timber harvesting is a problem, just reducing the amount of timber harvested won't provide as large of a benefit as the restriction of development of roads for snowmobiling and skiing. If bans were enforced to completely eliminate the harvesting of timber, then this would have the greatest benefit.

335) Which indirect value of biodiversity will have the greatest economical value to people? A) a twenty-hectare marshland that acts as a sponge for rainwater B) the ecotourismmarket in the United States C) two hundredhectares of wetlands in Canada that soak up pollutants and purify water D) forests that decrease erosion along the banks of rivers in the Philippines E) a row of trees that act as a wind block on the northwest side of our homes, decreasing our need for air conditioning and cooling systems in the summer

335) C It is estimated that one hectare of wetlands in Canada act to take up pollutants as well as purify water. Each hectare is valued at $50,000. If the forest contains two hundred hectares, this would equal approximately $10 billion dollars in value.

336) The main goal of conservation biology is to A) conserve natural resources for this and future generations. B) promote the needs of certain ecosystems that are determined to be in danger. C) prevent the hunting and fishing of species. D) prevent the building of large structures like shopping malls and businesses. E) promote the welfare of endangered species.

336) A Conservation biology is a field of biology that focuses on conserving natural resources for this and future generations. It is concerned with developing new scientific concepts and applying them to our lives, along with sustainably managing the Earth's biodiversity for human use.

337) Which subfield directly supports conservation biology? A) genetics B) ecology C) wildlife management D) field biology E) All of the subfields listed support conservation biology.

337) E Many subfields of biology support conservation biology.

338.1) At the area labeled "A" in the figure shown here, A) O 2 and CO 2 enter the lungs. B) O 2 and CO 2 leave the lungs. C) O 2 enters the lungs and CO 2 leaves the lungs. D) CO 2 enters the lungs and CO 2 leaves the lungs. E) nutrients move into the body and CO 2 leaves the body.

338.1) C Through breathing, air high in oxygen is brought into the lungs and air high in carbon dioxide is breathed out. From the air in the lungs, oxygen moves into the pulmonary capillaries in the lungs and out of the blood at the tissues. Carbon dioxide follows the opposite pathway. Exchange of gases between the blood in the pulmonary capillaries and the air in the lungs is called external respiration. Exchange of gases between the blood and the body tissues is called internal respiration.

338.2) In the figure shown here, "E" represents A) external respiration—the exchange of gases between the body tissues and the blood. B) external respiration—the exchange of gases between the blood and the air in the lungs. C) internal respiration—the exchange of gases between the body tissues and the blood. D) internal respiration—the exchange of gases between the blood and the air in the lungs. E) external respiration—the exchange of gases between the air in the lungs and the outside.

338.2) C Through breathing, air high in oxygen is brought into the lungs and air high in carbon dioxide is breathed out. From the air in the lungs, oxygen diffuses into the pulmonary capillaries in the lungs and out of the blood at the tissues. Carbon dioxide follows the opposite pathway. Exchange of gases between the blood in the pulmonary capillaries and the air in the lungs is called external respiration. Exchange of gases between the blood and the body tissues is called internal respiration.

339.1) The figure shown represents urine formation. What specific process is occurring at #2? A) secretion B) filtration C) reabsorption D) excretion E) urination

339.1) C Three processes are involved in the formation of urine in the nephrons of the kidney. During filtration, water and small particles move into the tubule. Substances are then reabsorbed into the blood or secreted from the blood into the urine.

339.2) The figure shown represents urine formation. Substances which move from the blood into the filtrate at #3 include A) glucose. B) amino acids. C) sodium ions. D) chloride ions. E) hydrogen ions.

339.2) E Three processes are involved in the formation of urine in the nephrons of the kidney. During filtration, water and small particles move into the tubule. Substances are then reabsorbed into the blood or secreted from the blood into the urine. Substances which are secreted into the filtrate in the distal tubule include hydrogen ion, uric acid, and ammonia.