Bio 102 Final Part 2

Question 74: Which arrow indicates the direction of a gradient of increasing solute concentration in the interstitial fluid surrounding a nephron? A only B only B and C C and D A and D

A only

Select the correct statement about osmoregulation. A. All osmoconformers are marine animals. B. The less the gradient between an animal's internal osmolarity and its external osmolarity (that of its surroundings), the higher the cost of osmoregulation. C. All marine invertebrates are stenohaline.

A. All osmoconformers are marine animals.

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

A. Only certain molecules can cross a cell membrane.

Select the correct statement about osmolarity. A. Osmolarity measures the moles of solute per liter of solution. B. The contents of an animal cell are hyperosmotic. C. If two solutions are separated by a selectively permeable membrane, water flows by osmosis from a hyperosmotic solution to a hypoosmotic one.

A. Osmolarity measures the moles of solute per liter of solution.

Select the correct statement describing the osmolarity of mammalian urine. A. The osmolarity of mammalian urine may vary over time. B. The osmolarity of mammalian urine varies little between species C. Mammalian urine is always hyperosmotic to blood.

A. The osmolarity of mammalian urine may vary over time.

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

A. filtration from the glomerular capillaries

In humans, the transport epithelial cells in the ascending loop of Henle _____. A. have plasma membranes of low permeability to water B. are not in contact with interstitial fluid C. are the largest epithelial cells in the body D. are not affected by high levels of nitrogenous wastes

A. have plasma membranes of low permeability to water

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

A. increase, and the urine would be isoosmotic compared to plasma

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

A. is mainly a consequence of blood pressure in the capillaries of the glomerulus

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

A. kangaroo rats

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

A. proteins and nucleic acids

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

A. sweating-induced dehydration increases plasma osmolarity

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

A. the precise control of the retention of water and electrolytes

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

A. the vasa recta

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

A. they operate an extensive set of active-transport ion pumps

Question 63: Filtrate is formed as fluid is forced through the walls of the glomerulus and, initially, collects in the structure indicated by the letter A B C D E

B

Aldosterone is _____. A. decreases water reabsorption in the kidneys B. a steroid hormone that reduces the amount of fluid excreted in the urine C. triggers the conversion of angiotensinogen into angiotensin II D. is released in great quantities when ethanol intoxication takes place E. a protein hormone that decreases blood pressure without changing blood volume

B. a steroid hormone that reduces the amount of fluid excreted in the urine

The structural component(s) of the mammalian nephron where the transcytosis of water increases due to the action of anti-diuretic hormone is/are the _____. A. nephrons B. collecting duct C. Bowman's capsules D. afferent and efferent arterioles E. glomeruli

B. collecting duct

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

B. filtration

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

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

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

B. selective reabsorption

Question 90: Examine the figure of a human nephron. Where and when does osmolarity of the filtrate increase? A. As the filtrate moves through the proximal tubule B. As the filtrate moves up to the cortex in the ascending limb of the loop C. As the filtrate moves down the descending limb of the loop of Henle

C. As the filtrate moves down the descending limb of the loop of Henle

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

C. a mouse species living in a desert

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

C. maintains homeostasis of pH in body fluids

As filtrate moves down the loop of Henle, the surrounding interstitial fluid becomes _____ concentrated than the filtrate, so _____ leaves the filtrate. A. more ... urea B. less ... urea C. more ... water D. less ... water E. less ... water and urea

C. more ... water

Which of these is the functional unit of a kidney? A. neuron B. villi C. nephron D. alveolus E. osteon

C. nephron

The _____ are the major blood vessels transporting blood to the kidneys. A. pulmonary arteries B. glomerulus C. renal arteries D. renal veins E. venae cavae

C. renal arteries

Urine formed by a kidney collects in the _____ before being drained from the kidney by the _____ and transported to the _____. A. urethra ... urinary bladder ... ureter B. renal pelvis ... medulla ... cortex C. renal pelvis ... ureter ...urinary bladder D. renal pelvis ... urethra ... urinary bladder E. ureter ... renal pelvis ... urinary bladder

C. renal pelvis ... ureter ...urinary bladder

Birds secrete uric acid as their nitrogenous waste because uric acid _____. A. can be reused by birds as a protein source B. is readily soluble in water C. requires little water for nitrogenous waste disposal, thus reducing body mass D. is metabolically less expensive to synthesize than other excretory products

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

The movement of substances from the blood into the proximal tubule is known as _____. A. filtration B. dialysis C. secretion D. reabsorption E. none of these

C. secretion

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 kidneys require higher than normal levels of hormones. C. The renal artery and vein are the main pathways regulating how much is produced by the kidneys. D. 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.

D. 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.

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

D. a drink with a combination of water and electrolytes

Glucose is removed from filtrate by _____. A. secretion B. diffusion C. dialysis D. active transport E. osmosis

D. active transport

The outer part of the kidney is the _____. A. medulla B. nephron C. lacteal D. cortex E. Bowman's capsule

D. cortex

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. additional filtration takes place along the loop of Henle C. the loop of Henle plays an important role in detoxification D. differential permeabilities of ascending and descending limbs of the loop of Henle are important in establishing an osmotic gradient

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

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

D. juxtamedullary nephrons

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

D. kidneys of vertebrates

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

D. urea is less toxic than ammonia

Question 63: The urethra is identified by the letter _____. A B C D E

E

Which of these is reabsorbed from filtrate? A. sodium chloride B. glucose C. water D. amino acids E. all of these

E. all of these

The movement of substances out of the glomerulus and into Bowman's capsule is referred to as _____. A. secretion B. reabsorption C. active transport D. ion pumping E. filtration

E. filtration

The most abundant solute in urine is _____. A. glucose B. water C. plasma proteins D. sodium chloride E. urea (and other nitrogenous wastes)

E. urea (and other nitrogenous wastes)

As a result of the non-selectivity of the kidney's filtration of small molecules, _____. A. urine is always much less concentrated than blood B. many useful substances are lost in the urine C. the proportions of all the substances in the blood are the same as in the urine D. the kidneys have little control over body fluid composition E. useful substances must be selectively reabsorbed

E. useful substances must be selectively reabsorbed

Question 66: The figure above shows a nephron. Filtration takes place in the structure labeled _____. a b c d

a