CH 44

The outer part of the kidney is the _____. medulla nephron lacteal cortex Bowman's capsule

cortex

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

All osmoconformers are marine animals.

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 only I and II only I and III only II and III I, II, and III

I, II, and III

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

Only certain molecules can cross a cell membrane.

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

Osmolarity measures the moles of solute per liter of solution.

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

The osmolarity of mammalian urine may vary over time.

Why are the renal artery and vein critical to the process of osmoregulation in vertebrates? The renal artery and vein are the main pathways regulating how much is produced by the kidneys. 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. The kidneys require constant and abnormally high oxygen supply to function. The kidneys require higher than normal levels of hormones.

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? bottled water that had been frozen to ensure that it would be as cold as possible caffeinated beverages bottled water kept at room temperature a drink with a combination of water and electrolytes

a drink with a combination of water and electrolytes

Which of the following animals generally has the lowest volume of urine production? a vampire bat a shark inhabiting the Mississippi River a marine bony fish a salmon in fresh water

a marine bony fish

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

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

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

filtration

Which process in the nephron is LEAST selective? reabsorption secretion active transport filtration

filtration

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

filtration from the glomerular capillaries

Excessive formation of uric acid crystals in humans leads to _____. a condition of insatiable thirst and excessive urine formation gout, a painful inflammatory disease that primarily affects the joints a condition called diabetes, where excessive urine formation occurs osteoarthritis, an inevitable consequence of aging

gout, a painful inflammatory disease that primarily affects the joints

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

increase, and the urine would be isoosmotic compared to plasma

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

is soluble in water

Compared to the seawater around them, most marine invertebrates are _____. hypoosmotic hyperosmotic and isoosmotic isoosmotic hyperosmotic

isoosmotic

The body fluids of an osmoconformer would be _____ with its _____ environment isoosmotic; saltwater hyperosmotic; saltwater isoosmotic; freshwater hypoosmotic; saltwate

isoosmotic; saltwater

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

juxtamedullary nephrons

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

kangaroo rats

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

kidneys of vertebrates

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

liver from NH3 and carbon dioxide

Ammonia is likely to be the primary nitrogenous waste in living conditions that include _____. lots of seawater, such as a bird living in a marine environment a terrestrial environment, such as that supporting crickets lots of fresh water flowing across the gills of a fish a moist system of burrows, such as those of naked mole rats

lots of fresh water flowing across the gills of a fish

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

maintains homeostasis of pH in body fluids

The _____ are the major blood vessels transporting blood to the kidneys. pulmonary arteries glomerulus renal arteries renal veins venae cavae

renal arteries

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

renal pelvis ... ureter ...urinary bladder

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

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

Materials are returned to the blood from the filtrate by which of the following processes? excretion selective reabsorption filtration secretion

selective reabsorption

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

sweating-induced dehydration increases plasma osmolarity

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

the precise control of the retention of water and electrolytes

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

they operate an extensive set of active-transport ion pumps

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

urea (and other nitrogenous wastes)

Which nitrogenous waste has the greatest number of nitrogen atoms? ammonia uric acid ammonium ions urea

uric acid

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

a mouse species living in a desert

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

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

Glucose is removed from filtrate by _____. secretion diffusion dialysis active transport osmosis

active transport

Which of these is reabsorbed from filtrate? sodium chloride glucose water amino acids all of these

all of these

Freshwater fish excrete nitrogenous wastes as _____. uric acid urea ammonia guano proteins

ammonia

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 _____. View Available Hint(s) collecting duct afferent and efferent arterioles Bowman's capsules nephrons glo

collecting duct

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

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

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

have plasma membranes of low permeability to water

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

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

Osmoregulation and excretion are _____. chemical processes that completely stop during torpor and hibernation ways that animals control their external environment mechanisms that require continual water loss mechanisms for the homeostatic control of body temperature mechanisms that maintain volume and composition of body fluids

mechanisms that maintain volume and composition of body fluids

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

more ... water

Which of these is the functional unit of a kidney? neuron villi nephron alveolus osteon

nephron

Birds, insects, and many reptiles excrete nitrogenous waste in the form of uric acid, which _____. reduces energy use compared to other nitrogenous wastes, but is highly toxic to animals that produce it is much more soluble in water than other nitrogenous wastes, but is energetically costlier than other nitrogenous wastes to synthesize reduces water loss compared to other nitrogenous wastes, but is highly toxic reduces water loss compared to other nitrogenous wastes, but requires more metabolic energy to produce is not very toxic compared to other nitrogenous wastes, but requires the loss of a lot of water with its excretion

reduces water loss compared to other nitrogenous wastes, but requires more metabolic energy to produce

The fluid with the highest osmolarity is _____. plasma in birds seawater in a tidal pool distilled water plasma in mammals

seawater in a tidal pool

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

secretion

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

selective elimination of excess ions and toxins from body fluids

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

the concentration gradient; ATP

Urea is _____. the primary nitrogenous waste product of humans insoluble in water the primary nitrogenous waste product of most aquatic invertebrates the primary nitrogenous waste product of most birds

the primary nitrogenous waste product of humans

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

the vasa recta

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

urea is less toxic than ammonia

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

useful substances must be selectively reabsorbed