Campbell Bio Ch 44

B

1) A marine sea star was mistakenly placed in freshwater and it died. What is the most likely explanation for its death? A) The sea star was stressed and needed more time to acclimate to new conditions. B) The sea star is hyperosmotic to the freshwater, and it could not osmoregulate. C) The osmoregulatory system of the sea star could not handle the change in ionic content presented by the freshwater. D) The contractile vacuoles used to regulate water content ruptured in the freshwater. E) The cells of the sea star dehydrated and lost the ability to metabolize.

C

10) Unlike most bony fishes, sharks maintain body fluids that are isoosmotic to seawater, so they are considered by many to be osmoconformers. Nonetheless, these sharks osmoregulate at least partially by A) using their gills and kidneys to rid themselves of sea salts. B) monitoring dehydration at the cellular level with special gated aquaporins. C) tolerating high urea concentrations that balance internal salt concentrations to seawater osmolarity. D) synthesizing trimethylamine oxide, a chemical that binds and precipitates salts inside cells. E) possessing a special adaptation that allows their cells to operate at an extraordinarily high salt concentration.

A

11) The necropsy (postmortem analysis) of a freshwater fish that died after being placed accidentally in saltwater would likely show that A) loss of water by osmosis from cells in vital organs resulted in cell death and organ failure. B) high amounts of salt had diffused into the fish's cells, causing them to swell and lyse. C) the kidneys were not able to keep up with the water removal necessary in this hyperosmotic environment, creating an irrevocable loss of homeostasis. D) the gills became encrusted with salt, resulting in inadequate gas exchange and a resulting asphyxiation. E) brain cells lysed as a result of increased osmotic pressure in this hyperosmotic environment, leading to death by loss of autonomic function.

A

12) Urea is produced in the A) liver from NH₃ and CO₂. B) liver from glycogen. C) kidneys from glucose. D) kidneys from glycerol and fatty acids. E) bladder from uric acid and H₂O.

D

14) Which nitrogenous waste has the greatest number of nitrogen atoms? A) ammonia B) ammonium ions C) urea D) uric acid

A

15) Ammonia is likely to be the primary nitrogenous waste in living conditions that include A) lots of fresh water flowing across the gills of a fish. B) lots of seawater, such as a bird living in a marine environment. C) lots of seawater, such as a marine mammal (e.g., a polar bear). D) a terrestrial environment, such as that supporting crickets. E) a moist system of burrows, such as those of naked mole rats.

D

17) The nitrogenous waste that requires the most energy to produce is A) ammonia. B) ammonium. C) urea. D) uric acid.

C

18) Excessive formation of uric acid crystals in humans leads to A) a condition called diabetes, where excessive urine formation occurs. B) a condition of insatiable thirst and excessive urine formation. C) gout, a painful inflammatory disease that primarily affects the joints. D) the absence of urea in the urine. E) osteoarthritis, an inevitable consequence of aging.

B

2) Organisms categorized as osmoconformers are most likely A) found in freshwater lakes and streams. B) marine. C) amphibious. D) found in arid terrestrial environments. E) found in terrestrial environments with adequate moisture.

B

20) The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that A) urea can be exchanged for Na+. B) urea is less toxic than ammonia. C) urea requires more water for excretion than ammonia. D) urea does not affect the osmolar gradient. E) less nitrogen is removed from the body.

E

21) The primary nitrogenous waste excreted by birds is A) ammonia. B) nitrate. C) nitrite. D) urea. E) uric acid.

C

24) Birds secrete uric acid as their nitrogenous waste because uric acid A) is readily soluble in water. B) is metabolically less expensive to synthesize than other excretory products. C) requires little water for nitrogenous waste disposal, thus reducing body mass. D) excretion allows birds to live in desert environments.

C

26) Materials are returned to the blood from the filtrate by which of the following processes? A) filtration B) ultrafiltration C) selective reabsorption D) secretion E) active transport

A

27) Excretory structures known as protonephridia are present in A) flatworms. B) earthworms. C) insects. D) vertebrates. E) cnidarians.

A

29) The osmoregulatory/excretory system of a freshwater flatworm is based on the operation of A) protonephridia. B) metanephridia. C) Malpighian tubules. D) nephrons. E) ananephredia.

D

3) The body fluids of an osmoconformer would be ________ with its ________ environment. A) hyperosmotic; freshwater B) isotonic; freshwater C) hyperosmotic; saltwater D) isoosmotic; saltwater E) hypoosmotic; saltwater

E

30) Freshwater flatworms form a urine that is typically A) of high solute concentration, in order to conserve body fluids. B) of very low volume, in order to conserve body fluids. C) of high solute concentration and very low volume, in order to conserve body fluids. D) of high solute concentration and of high volume, matching their normal fluid uptake. E) of low solute concentration and of high volume, matching their normal fluid uptake.

B

32) The osmoregulatory/excretory system of an earthworm is based on the operation of A) protonephridia. B) metanephridia. C) Malpighian tubules. D) nephrons. E) ananephredia.

C

33) The osmoregulatory/excretory system of an insect is based on the operation of A) protonephridia. B) metanephridia. C) Malpighian tubules. D) nephrons. E) ananephredia.

E

35) Choose a pair that correctly associates the mechanism for osmoregulation or nitrogen removal with the appropriate animal. A) metanephridiumflatworm B) Malpighian tubulefrog C) kidneyinsect D) flame bulbsnake E) direct cellular exchangemarine invertebrate

E

36) An excretory system that is partly based on the filtration of fluid under high hydrostatic pressure is the A) flame bulb system of flatworms. B) protonephridia of rotifers. C) metanephridia of earthworms. D) Malpighian tubules of insects. E) kidneys of vertebrates.

A

38) Within a normally functioning kidney, blood can be found in A) the vasa recta. B) Bowman's capsule. C) the loop of Henle. D) the proximal tubule. E) the collecting duct

B

39) A person with alkalosis will likely excrete urine that has abnormally high levels of A) bicarbonate ions. B) sodium ions. C) glucose. D) ammonia. E) NaOH.

A

41) Juxtamedullary nephrons can concentrate salt effectively in the renal medulla because of their long A) loops of Henle. B) distal convoluted tubules. C) Bowman's capsules. D) proximal convoluted tubules. E) glomeruli.

C

42) The filtrate in the proximal convoluted tubule of the human does not normally include A) ions. B) glucose. C) plasma proteins. D) amino acids. E) dissolved gasses.

A

44) The osmolarity of human urine A) can be four times as great as normal osmolarity of human plasma. B) is always exactly equal to plasma osmolarity. C) is always less than plasma osmolarity. D) is always greater than plasma osmolarity. E) is determined primarily by the concentration of glucose.

C

45) A primary reason that the kidneys have one of the highest metabolic rates of all body organs is that A) it stores the body's excess fats. B) it has membranes of varying permeability to water. C) it operates an extensive set of active-transport ion pumps. D) it is the body's only means of shedding excess nutrients. E) it has an abundance of myogenic smooth muscle.

C

47) If ATP production in a human kidney was suddenly halted, urine production would A) come to a complete halt. B) decrease, and the urine would be hypoosmotic compared to plasma. C) increase, and the urine would be isoosmotic compared to plasma. D) increase, and the urine would be hyperosmotic compared to plasma. E) decrease, and the urine would be isoosmotic compared to plasma.

C

5) The fluid with the highest osmolarity is A) distilled water. B) plasma in birds. C) plasma in mammals. D) seawater in a tidal pool. E) estuarine water.

C

50) In humans, the transport epithelial cells in the ascending loop of Henle A) are the largest epithelial cells in the body. B) are not in contact with interstitial fluid. C) have plasma membranes of low permeability to water. D) have 50% of their cell mass made of smooth endoplasmic reticulum. E) are not affected by high levels of nitrogenous wastes.

D

51) The typical osmolarity of human blood is A) 30 mosm/L. B) 100 mosm/L. C) 200 mosm/L. D) 300 mosm/L. E) 500 mosm/L.

E

53) When stimulated by aldosterone, the reabsorption of Na+ is increased along A) the loop of Henle. B) the collecting duct. C) Bowman's capsule. D) the proximal tubule. E) the distal tubule.

B

54) Increased ADH secretion is likely after A) drinking lots of pure water. B) sweating-induced dehydration increases plasma osmolarity. C) ingestion of ethanol (drinking alcoholic drinks). D) eating a small sugary snack. E) blood pressure is abnormally high.

C

55) After blood flow is artificially reduced at one kidney, you would expect that kidney to secrete more of the hormone known as A) erythropoietin. B) angiotensinogen. C) renin. D) antidiuretic hormone. E) atrial natriuretic peptide.

C

56) After drinking alcoholic beverages, increased urine excretion is the result of A) increased aldosterone production. B) increased blood pressure. C) inhibited secretion of antidiuretic hormone (ADH). D) increased reabsorption of water in the proximal tubule. E) the osmoregulator cells of the brain increasing their activity.

B

57) Osmoregulatory adjustment via the renin-angiotensin-aldosterone system can be triggered by A) sleeping for one hour. B) severe sweating on a hot day. C) eating a bag of potato chips. D) eating a pizza with olives and pepperoni. E) drinking several glasses of water.

B

59) ADH and RAAS work together in maintaining osmoregulatory homeostasis through which of the following ways? A) ADH regulates the osmolarity of the blood and RAAS regulates the volume of the blood. B) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and RAAS maintains the osmolarity of the blood by stimulating Na+ reabsorption. C) ADH and RAAS work antagonistically; ADH stimulates water reabsorption during dehydration and RAAS causes increased excretion of water when it is in excess in body fluids. D) both stimulate the adrenal gland to secrete aldosterone, which increases both blood volume and pressure via its receptors in the urinary bladder. E) by combining at the receptor sites of proximal tubule cells, where reabsorption of essential nutrients takes place.

C

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) using their gills and kidneys to rid themselves of sea salts. B) monitoring dehydration at the cellular level with special gated aquaporins. C) tolerating high urea concentrations that balance internal salt concentrations to sea water osmolarity. D) synthesizing trimethylamine oxide, a chemical that speeds salt removal from cells. E) possessing a special adaptation that allows their cells to operate at an unusually high salt concentration.

A

63) In a laboratory experiment with three groups of students, one group 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. Which groups are expected to have the greatest and least amounts of urine, respectively? A) Beer drinkers have the most; salt solution drinkers have the least. B) Salt solution drinkers have the most; water drinkers have the least. C) Water drinkers have the most; beer drinkers have the least. D) Beer drinkers have the most; water drinkers have the least. E) There will be no significant difference between these groups.

A

65) Which process in the nephron is least selective? A) filtration B) reabsorption C) active transport D) secretion E) salt pumping by the loop of Henle

C

66) Which of the following animals generally has the lowest volume of urine production? A) a vampire bat B) a salmon in fresh water C) a marine bony fish D) a freshwater bony fish E) a shark inhabiting freshwater Lake Nicaragua

D

68) Natural selection should favor the highest proportion of juxtamedullary nephrons in which of the following species? A) a river otter B) a mouse species living in a tropical rain forest C) a mouse species living in a temperate broadleaf forest D) a mouse species living in a desert E) a beaver

B

69) African lungfish, which are often found in small stagnant pools of fresh water, produce urea as a nitrogenous waste. What is the advantage of this adaptation? A) Urea takes less energy to synthesize than ammonia. B) Small stagnant pools do not provide enough water to dilute the toxic ammonia. C) The highly toxic urea makes the pool uninhabitable to potential competitors. D) Urea forms an insoluble precipitate. E) Urea makes lungfish tissue hypoosmotic to the pool.

B

7) Osmoconforming sharks take in water, as needed, A) by migrating to freshwater rivers to drink fresh water. B) via osmosis, as their body cells are slightly hyperosmotic to seawater. C) via active transport of water across the cells on their gills. D) by water diffusion from seawater, which is hyperosmotic to the fluids in their cells. E) by selective transport of water molecules across the wall of the gut

B

8) A human who has no access to fresh water but is forced to drink seawater instead A) will thrive under such conditions, as long as he has lived at the ocean most of his life. B) will excrete more water molecules than taken in, because of the high load of ion ingestion. C) will develop structural changes in the kidneys to accommodate the salt overload. D) will find that drinking saltwater satiates his thirst. E) will risk becoming overhydrated within 12 hours.

E

9) Many marine and freshwater bony fish achieve osmoregulation via A) loss of water through the gills. B) gain of salt through the gills. C) loss of water in the urine. D) no drinking of water. E) gain of water through food.

A

Use the following structural formulas to identify the following items 60) Which of the following is excreted readily by aquatic animals because of its solubility and toxicity properties A) A B) B C) C D) D E) E

C

Use the following structural formulas to identify the following items 62) Which of the following is excreted as a paste by land snails, insects, birds, and many reptiles, because of its solubility and toxicity properties? A) A B) B C) C D) D E) E

B

Use the following structural formulas to identify the following items Synthesized by mammals, most amphibians, sharks, and some bony fishes because of its lesser toxicity