Biology Chapter 44

B) excrete more water molecules than taken in, because of the high load of ion ingestion

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

B) it was so hypertonic to the fresh water that it could not osmoregulate

A necropsy (postmortem analysis) of a marine sea star that died after it was mistakenly placed in fresh water would likely show that it died because _____. A) it was stressed and needed more time to acclimate to the new conditions B) it was so hypertonic to the fresh water that it could not osmoregulate C) its contractile vacuoles ruptured D) its cells dehydrated and lost the ability to metabolize

C) There would be a net movement of water into the lumen of the tubules.

A potassium ion gradient is set up in insect Malpighian tubules through an active transport process. As a result, potassium concentration is higher in the lumen of the tubules than in hemolymph. How would the potassium gradient affect water movement? A) Water would be forced out of the lumen of the Malpighian tubules through an osmotic gradient. B) The potassium gradient would have no effect on water movement. C) There would be a net movement of water into the lumen of the tubules. D) Water would be conserved, forming a hypertonic solution in the Malpighian tubules.

B) they operate an extensive set of active-transport ion pumps

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

B) Small, stagnant pools do not provide enough water to dilute the toxic ammonia. (Ammonia is generally produced by freshwater species because they have ample water available to dilute the ammonia. In this situation, they have little water so available so they produce urea.)

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 makes lungfish tissue hypoosmotic to the pool.

B) renin

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

C) inhibited secretion of antidiuretic hormone (ADH)

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

A) is soluble in water

Ammonia _____. A) is soluble in water B) has low toxicity relative to urea C) is metabolically more expensive to synthesize than urea D) is the major nitrogenous waste excreted by insects

A) lots of fresh water flowing across the gills of a fish

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) a terrestrial environment, such as that supporting crickets D) a moist system of burrows, such as those of naked mole rats

B) kangaroo rats

Among the following choices, the most concentrated urine is excreted by _____. A) frogs B) kangaroo rats C) humans D) freshwater bass

D) kidneys of vertebrates

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) Malpighian tubules of insects D) kidneys of vertebrates

A) ADH regulates the osmolarity of the blood by altering renal reabsorption of water, and the RAAS maintains the osmolarity of the blood by stimulating Na+ and water reabsorption.

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

C) requires little water for nitrogenous waste disposal, thus reducing body mass

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) can be reused by birds as a protein source

D) exchange across the body surface — marine invertebrate

Choose a pair that correctly associates the mechanism for osmoregulation or nitrogen removal with the appropriate animal. A) metanephridium — flatworm B) Malpighian tubule — frog C) flame bulb — snake D) exchange across the body surface — marine invertebrate

C) isoosmotic

Compared to the seawater around them, most marine invertebrates are _____. A) hyperosmotic B) hypoosmotic C) isoosmotic D) hyperosmotic and isoosmotic

A) juxtamedullary nephrons

Compared to wetland mammals, water conservation in mammals of arid regions is enhanced by having more _____. A) juxtamedullary nephrons B) urinary bladders C) ureters D) podocytes

C) gout, a painful inflammatory disease that primarily affects the joints

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) osteoarthritis, an inevitable consequence of aging

B) insects

Excretory organs known as Malpighian tubules are present in _____. A) flatworms B) insects C) jellyfish D) sea stars

D) Hagfish habitat is limited by the salinity of the environment.

Hagfish (Eptatretus cirrhauts) are a jawless marine vertebrate that are isotonic with their environment and are considered to be osmoconformers. How might this interesting adaptation limit the habitat that the hagfish can tolerate? A) Hagfish are not limited by salinity. B) Osmoconformers do not face the same pressures as osmoregulators and can live in any marine environment. C) Individual hagfish will adapt to different salinities over their lifetime and, therefore, can inhabit any marine environment. D) Hagfish habitat is limited by the salinity of the environment.

B) increase, and the urine would be isoosmotic compared to plasma

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

A) a drink with a combination of water and electrolytes

If you are hiking through the desert for several days, one would pack which of the following to ensure proper hydration? A) a drink with a combination of water and electrolytes B) caffeinated beverages C) bottled water kept at room temperature D) bottled water that had been frozen to ensure that it would be as cold as possible

C) proteins and nucleic acids

In animals, nitrogenous wastes are produced mostly from the catabolism of _____. A) starch and cellulose B) triglycerides and steroids C) proteins and nucleic acids D) phospholipids and glycolipids

C) have plasma membranes of low permeability to water

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) are not affected by high levels of nitrogenous wastes

B) sweating-induced dehydration increases plasma osmolarity

Increased antidiuretic hormone (ADH) secretion is likely after _____. A) drinking lots of pure water B) sweating-induced dehydration increases plasma osmolarity C) eating a small sugary snack D) blood pressure becomes abnormally high

C) filtration from the glomerular capillaries

Low selectivity of solute movement is a characteristic of _____. A) H+ pumping to control pH B) reabsorption mechanisms along the proximal tubule C) filtration from the glomerular capillaries D) secretion along the distal tubule

B) selective reabsorption

Materials are returned to the blood from the filtrate by which of the following processes? A) filtration B) selective reabsorption C) secretion D) excretion

D) a mouse species living in a desert

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

D) I, II, and III

One of the waste products that accumulates during cellular functions is carbon dioxide. It is removed via the respiratory system. What is another waste product that accumulates during normal physiological functions in vertebrates? I) ammonia II) uric acid III) urea A) only I and III B) only II and III C) only I and II D) I, II, and III

B) severe sweating on a hot day

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 pizza with olives and pepperoni D) drinking several glasses of water

B) maintains homeostasis of pH in body fluids

Processing of filtrate in the proximal and distal tubules _____. A) achieves the conversion of toxic ammonia to less toxic urea B) maintains homeostasis of pH in body fluids C) regulates the speed of blood flow through the nephrons D) reabsorbs urea to maintain osmotic balance

B) Different gill cells are involved in osmoregulation in freshwater than in salt water.

Salmon eggs hatch in freshwater. The fish then migrate to the ocean (a hypertonic solution) and, after several years of feeding and growing, return to freshwater to breed. How can these organisms make the transition from freshwater to ocean water and back to freshwater? A) The rectal gland functions in the ocean water, and chloride cells function in freshwater. B) Different gill cells are involved in osmoregulation in freshwater than in salt water. C) Salmon in freshwater excrete dilute urine, and salmon in salt water secrete concentrated urine. D) Their metabolism changes in salt water to degrade electrolytes.

A) Urea and trimethylamine oxide contribute to intra- and extracellular osmolarity in shark tissues.

Sharks live in seawater. Their tissues are isotonic to seawater, but their concentrations of sodium ions, potassium ions, and chloride ions in cells and extracellular fluids are similar to those of freshwater fishes. How is that possible? A) Urea and trimethylamine oxide contribute to intra- and extracellular osmolarity in shark tissues. B) Metabolic intermediates of sharks tie up intracellular chloride and potassium ions. C) Their blood is hypotonic to their tissues. D) They excrete large quantities of electrolytes.

A) 0.0 mM sucrose

Single-celled Paramecium live in pond water (a hypotonic environment). They have a structural feature, a contractile vacuole, which enables them to osmoregulate. If you observed them in the following solutions, at which sucrose concentration (in millimolars, mM) would you expect the contractile vacuole to be most active? A) 0.0 mM sucrose B) 0.05 mM saline C) 0.08 mM sucrose D) 1.0 mM saline

B) desert

Terrestrial organisms lose water through evaporation. In what ecosystem might an entomologist find a good study organism to examine the prevention of water loss? A) wet rain forest B) desert C) prairie D) chaparral

B) urea is less toxic than ammonia

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 does not affect the osmolar gradient D) less nitrogen is removed from the body

C) isoosmotic; saltwater

The body fluids of an osmoconformer would be _____ with its _____ environment A) isoosmotic; freshwater B) hyperosmotic; saltwater C) isoosmotic; saltwater D) hypoosmotic; saltwater

A) a

The figure above shows a nephron. Filtration takes place in the structure labeled _____. A) a B) b C) c D) d

D) seawater in a tidal pool

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

B) the concentration gradient; ATP

The force driving simple diffusion is _____, while the energy source for active transport is _____. A) the concentration gradient; ADP B) the concentration gradient; ATP C) transmembrane pumps; electron transport D) phosphorylated protein carriers; ATP

D) diffusion of salt from the descending limb of the loop of Henle

The high osmolarity of the renal medulla is maintained by all of the following EXCEPT _____. A) active transport of salt from the upper region of the ascending limb B) the spatial arrangement of juxtamedullary nephrons C) diffusion of urea from the collecting duct D) diffusion of salt from the descending limb of the loop of Henle

B) differential permeabilities of ascending and descending limbs of the loop of Henle are important in establishing an osmotic gradient

The loop of Henle dips into the renal cortex. This is an important feature of osmoregulation in terrestrial vertebrates because _____. A) absorptive processes taking place in the loop of Henle are hormonally regulated B) differential permeabilities of ascending and descending limbs of the loop of Henle are important in establishing an osmotic gradient C) the loop of Henle plays an important role in detoxification D) additional filtration takes place along the loop of Henle

A) loss of water by osmosis from cells in vital organs resulted in cell death and organ failure

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

B) selective elimination of excess ions and toxins from body fluids

The osmoregulatory process called secretion refers to the _____. A) reabsorption of nutrients from a filtrate B) selective elimination of excess ions and toxins from body fluids C) formation of an osmotic gradient along an excretory structure D) expulsion of urine from the body

A) protonephridia

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

B) metanephridia

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

D) is mainly a consequence of blood pressure in the capillaries of the glomerulus

The transfer of fluid from the glomerulus to Bowman's capsule _____. A) results from active transport B) transfers large molecules as easily as small ones C) is very selective as to which subprotein-sized molecules are transferred D) is mainly a consequence of blood pressure in the capillaries of the glomerulus

B) Movement of potassium into the lumen of the Malpighian tubules is an energy-requiring process.

Through studies of insect Malpighian tubules, researchers found that K+ accumulated on the inner face of the tubule, against its concentration gradient. What can you infer about the mechanism of transport? A) Potassium transport is a passive process. B) Movement of potassium into the lumen of the Malpighian tubules is an energy-requiring process. C) Potassium moves out of the tubules at a faster rate than it moves into the lumen of the tubules. D) Sodium ions will follow potassium ions.

B) Sodium and chloride will diffuse into shark gills from seawater down their concentration gradient.

Tissues of sharks are isotonic to seawater, but their concentrations of sodium ions, potassium ions, and chloride ions in cells and extracellular fluids are similar to those of freshwater fishes. What can you infer about the movement of sodium and chloride in these animals? A) To maintain homeostasis of sodium and chloride levels, the shark must take up additional sodium and chloride from seawater. B) Sodium and chloride will diffuse into shark gills from seawater down their concentration gradient. C) Sharks conserve sodium and chloride, limiting excretion. D) Sodium and chloride must be eliminated through the gills.

C) excrete large quantities of water

To maintain homeostasis freshwater fish must _____. A) excrete large quantities of electrolytes B) consume large quantities of water C) excrete large quantities of water D) take in electrolytes through simple diffusion

C) tolerating high urea concentrations that are balanced with internal salt concentrations to seawater osmolarity

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 are balanced with internal salt concentrations to seawater osmolarity D) synthesizing trimethylamine oxide, a chemical that binds and precipitates salts inside cells

B) the primary nitrogenous waste product of humans

Urea is _____. A) insoluble in water B) the primary nitrogenous waste product of humans C) the primary nitrogenous waste product of most birds D) the primary nitrogenous waste product of most aquatic invertebrates

A) liver from NH3 and carbon dioxide

Urea is produced in the _____. A) liver from NH3 and carbon dioxide B) liver from glycogen C) kidneys from glycerol and fatty acids D) bladder from uric acid and water

B) the precise control of the retention of water and electrolytes

What is the function of the osmotic gradient found in the kidney? The osmotic gradient allows for _____. A) electrolytes to move from low to high concentrations in the absence of ATP B) the precise control of the retention of water and electrolytes C) the loop of Henle to deliver water to the renal vein D) the filtration of large cells at the glomerulus

C) They are involved in excretion of excess salt.

What role do chloride cells play in osmoregulation of marine fish with bony skeletons? A) They actively transport chloride into the gills. B) They mediate the movement of salt from seawater through their gills. C) They are involved in excretion of excess salt. D) They actively transport salt across the basolateral membrane of the rectal gland.

D) uric acid

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

C) a marine bony fish

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 shark inhabiting the Mississippi River

D) Only certain molecules can cross a cell membrane.

Which of the following most accurately describes selective permeability? A) An input of energy is required for transport. B) Lipid-soluble molecules pass through a membrane. C) There must be a concentration gradient for molecules to pass through a membrane. D) Only certain molecules can cross a cell membrane.

A) filtration

Which process in the nephron is LEAST selective? A) filtration B) reabsorption C) active transport D) secretion

B) The renal artery delivers blood with nitrogenous waste to the kidney and the renal vein brings blood with less nitrogenous wastes away from the kidneys.

Why are the renal artery and vein critical to the process of osmoregulation in vertebrates? A) The kidneys require constant and abnormally high oxygen supply to function. B) The renal artery delivers blood with nitrogenous waste to the kidney and the renal vein brings blood with less nitrogenous wastes away from the kidneys. C) The kidneys require higher than normal levels of hormones. D) The renal artery and vein are the main pathways regulating how much is produced by the kidneys.

A) the vasa recta

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