AP Exam Chapters 44 Osmosregulation and 45 Hormones and the Endocrine System Name SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. Use the following structural formulas to identify the following items. Figure 44.1 1) Synthesized by mammals, most amphibians, sharks, and some bony fishes because of its lesser toxicity 1) MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 2) Which of the following nitrogenous wastes requires hardly any water for its excretion? 2) A) urea B) uric acid C) ammonia D) nitrogen gas E) amino acid 3) The most concentrated urine is excreted by 3) A) frogs. B) birds. C) desert tortoises. D) kangaroo rats. E) humans. 1
4) In a laboratory experiment with three groups, one group of people drinks pure water, a second group drinks an equal amount of beer, and a third group drinks an equal amount of concentrated salt solution all during the same time period. Their urine production is monitored for several hours. At the end of the measurement period, which group will have produced the greatest volume of urine and which group the least? A) salt solution the most, water the least B) beer the most, water the least C) beer the most, salt solution the least D) water the most, beer the least E) There will be no significant difference between these groups. 4) 5) Which structure increases the reabsorption of Na+ when stimulated by aldosterone? 5) A) proximal tubule B) loop of Henle C) distal tubules D) collecting duct E) Bowman's capsule 6) Unlike most bony fishes, sharks maintain body fluids that are isoosmotic to sea water. They are therefore considered by many to be osmoconformers because of the unusual way they maintain homeostasis. They osmoregulate by A) tolerating high urea concentrations that balance internal salt concentrations to sea water osmolarity. B) using their gills and kidneys to rid themselves of sea salts. C) possessing a special adaptation that allows their cells to operate at an unusually high salt concentration. D) monitoring dehydration at the cellular level with special gated aquaporins. E) synthesizing trimethylamine oxide, a chemical that speeds salt removal from cells. 6) 7) Unlike an earthworm's metanephridia, a mammalian nephron 7) A) receives filtrate from blood instead of coelomic fluid. B) is intimately associated with a capillary network. C) has a transport epithelium. D) forms urine by changing fluid composition inside a tubule. E) functions in both osmoregulation and excretion. 8) Which of the following activities would initiate an osmoregulatory adjustment brought about primarily through the renin-angiotensin-aldosterone system? A) eating a pizza with olives and pepperoni B) spending several hours mowing the lawn on a hot day C) drinking several glasses of water D) sleeping E) eating a bag of potato chips 8) 9) What is the main nitrogenous waste excreted by birds? 9) A) nitrite B) uric acid C) nitrate D) ammonia E) urea 2
10) Which of the following excretory systems is partly based on the filtration of fluid under high hydrostatic pressure? A) protonephridia of rotifers B) Malpighian tubules of insects C) kidneys of vertebrates D) flame-bulb system of flatworms E) metanephridia of earthworms 10) 11) Which of the following would contain blood in a normally functioning nephron? 11) A) vasa recta B) Bowman's capsule C) proximal tubule D) collecting duct E) loop of Henle 12) Which feature of osmoregulation is found in both marine and freshwater bony fish? 12) A) loss of water in the urine B) gain of water through food C) gain of salt through the gills D) no drinking of water E) loss of water through the gills 13) Birds secrete uric acid as their nitrogenous waste because uric acid 13) A) is metabolically less expensive to synthesize than other excretory products. B) is readily soluble in water. C) requires little water for nitrogenous waste disposal which is conducive to the function of flight in terms of weight. D) excretion allows birds to live in desert environments. 3
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. Use the following structural formulas to identify the following items. Figure 44.1 14) Excreted mostly by aquatic animals because of its solubility and toxicity properties 14) MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 15) Which group possess excretory structures known as protonephridia? 15) A) earthworms B) flatworms C) cnidarians D) vertebrates E) insects 16) What is the typical osmolarity of human blood? 16) A) 30 mosm/l B) 200 mosm/l C) 100 mosm/l D) 500 mosm/l E) 300 mosm/l 17) Which structure passes urine to the renal pelvis? 17) A) loop of Henle B) proximal tubule C) collecting duct D) glomerulus E) Bowman's capsule 4
18) In animals, nitrogenous wastes are produced mostly from the catabolism of 18) A) proteins and nucleic acids. B) phospholipids and glycolipids. C) fatty acids and glycerol. D) starch and cellulose. E) triglycerides and steroids. 19) Which of the following is true of urea? It is 19) A) the primary nitrogenous waste product of most aquatic invertebrates. B) insoluble in water. C) the primary nitrogenous waste product of humans. D) the primary nitrogenous waste product of most birds. E) more toxic to human cells than ammonia. 20) Proper functioning of the human kidney requires considerable active transport of sodium in the kidney tubules. If these active transport mechanisms were to stop completely, how would urine production be affected? A) A less-than-normal volume of hypoosmotic urine would be produced. B) No urine would be produced. C) A greater-than-normal volume of isoosmotic urine would be produced. D) A greater-than-normal volume of hyperosmotic urine would be produced. E) A less-than-normal volume of isoosmotic urine would be produced. 20) 21) A distinctive feature of the mechanism of action of thyroid hormones and steroid hormones is that A) these hormones affect metabolism. B) target cells react more rapidly to these hormones than to local regulators. C) these hormones bind with specific receptor proteins on the plasma membrane of target cells. D) these hormones bind to receptors inside cells. E) these hormones are regulated by feedback loops. 21) 22) Only certain cells in the body are target cells for the steroid hormone aldosterone. Which of the following is the best explanation for why these are the only cells that respond to this hormone? A) Nontarget cells convert aldosterone to a hormone to which they do respond. B) Only target cells are exposed to aldosterone. C) Nontarget cells destroy aldosterone before it can produce its effect. D) Aldosterone is unable to enter nontarget cells. E) Only target cells contain receptors for aldosterone. 22) 23) Prolactin stimulates mammary gland growth and development in mammals and regulates salt and water balance in freshwater fish. Many scientists think that this wide range of functions indicates which of the following? A) Prolactin is an evolutionary conserved hormone. B) Prolactin has a unique mechanism for eliciting its effects. C) Prolactin is a nonspecific hormone. D) Prolactin interacts with many different receptor molecules. E) Prolactin is derived from two separate sources. 23) 5
24) Epinephrine is an example of 24) A) a catecholamine. B) an androgen. C) an estrogen. D) a progestin. E) melatonin. 25) Which of the following have nontropic effects only? 25) A) MSH B) LH C) FSH D) TSH E) ACTH 26) What do nitric oxide and epinephrine have in common? 26) A) They both function as hormones. B) They both function as neurotransmitters. C) They are both involved in the "fight-or-flight" response. D) They bind the same receptors. E) Only A and B are correct. 27) The relationship between the insect hormones ecdysone and PTTH 27) A) demonstrates that peptide-derived hormones have more widespread effects than steroid hormones. B) demonstrates competitive inhibition for the hormone receptor. C) illustrates homeostasis achieved by positive feedback. D) illustrates homeostasis maintained by antagonistic hormones. E) is an example of the interaction between the endocrine and nervous systems. 28) The main target organs for tropic hormones are 28) A) kidneys. B) nerves. C) muscles. D) blood vessels. E) endocrine glands. 29) One reason a person might be severely overweight is due to 29) A) an undersecretion of thyroxine. B) hyposecretion of oxytocin. C) a defect in hormone release from the posterior pituitary. D) a lower than normal level of insulin-like growth factors. E) a higher than normal level of melatonin. 30) Which of the following examples is incorrectly paired with its class? 30) A) neurotransmitter-local regulator B) estrogen-steroid hormone C) cytokines-local regulator D) ecdysone-steroid hormone E) prostaglandin-peptide hormone 6
31) Blood samples taken from an individual who had been fasting for 24 hours would have which of the following? A) high levels of insulin B) high levels of glucagon C) low levels of insulin D) low levels of glucagon E) both B and C 31) 32) Which of the following statements about hormones is incorrect? 32) A) They elicit specific biological responses from target cells. B) They are carried by the circulatory system. C) They are modified amino acids, peptides, or steroid molecules. D) They are used to communicate between different organisms. E) They are produced by endocrine glands. 33) The secretion of hormone A causes a change in the amount of protein X in an organism. If this mechanism works by positive feedback, which of the following statements represents that fact? A) An increase in X produces a decrease in A. B) A decrease in A produces an increase in X. C) An increase in A produces an increase in X. D) A and B are correct. E) B and C are correct. 33) 34) If the adrenal cortex were removed, which group of hormones would be most affected? 34) A) paracrine B) tropic C) steroid D) amino acid-derived E) peptide 35) Which of the following hormones is incorrectly paired with its action? 35) A) oxytocin stimulates uterine contractions during childbirth B) melatonin affects biological rhythms, seasonal reproduction C) insulin stimulates glycogen breakdown in the liver D) ACTH stimulates the release of glucocorticoids by the adrenal cortex E) thyroxine stimulates metabolic processes 36) Estradiol is an example of 36) A) an androgen. B) melatonin. C) an estrogen. D) a progestin. E) a catecholamine. 7
37) Which of the following hormones is (are) secreted by the adrenal gland in response to stress and promote(s) the synthesis of glucose from noncarbohydrate substrates? A) epinephrine B) ACTH C) thyroxine D) glucocorticoids E) glucagon 37) 38) Which of the following glands shows both endocrine and exocrine activity? 38) A) pancreas B) parathyroid C) pituitary D) adrenal E) salivary 39) The star of a recent movie was a caterpillar that never matured into an adult. It simply got larger with each molt. What is the probable reason why the caterpillar did not mature into an adult? A) lack of juvenile hormone B) increased level of juvenile hormone C) decreased level of ecdysone D) lack of ecdysone E) lack of the melatonin hormone 39) 40) Which combination of gland and hormone would be linked to winter hibernation and spring reproduction in bears? A) anterior pituitary gland, gonadotropin-releasing hormone B) pineal gland, estrogen C) hypothalamus gland, melatonin D) posterior pituitary gland, thyroid-stimulating hormone E) pineal gland, melatonin 40) 8