expend considerable energy in matching concentrations of their body fluids with those of their marine environment
	rely on the digestive, respiratory, and excretory systems to remove excess salts and water from their bodies
	have an internal environment isoosmotic with their external environment, which does not require expending energy
	spontaneously absorb water through the body surface and lose solutes in urine
	spontaneously lose water through body surfaces and must actively unload ions and drink water to maintain osmotic homeostasis

	experience no net water loss by osmosis
	experience significant water gain by osmosis
	experience significant water loss by osmosis
	must expend energy on the active transport of solutes from their bodies to the environment
	do not exist

	osmoconformers in seawater
	euryhaline animals in fresh water
	stenohaline animals that move between fresh water and seawater
	osmoregulators in seawater
	euryhaline animals in seawater

	Because they live in a hypoosmotic solution, their cells take up excess water that must be excreted.
	Because they live in a hypoosmotic solution, their cells tend to accumulate a lot of solute that must be excreted.
	Because they live in a hyperosmotic solution, their cells take up an excess of water that must be excreted.
	Because they live in a hyperosmotic solution, their cells tend to accumulate a lot of solute that must be excreted.
	Because animals must live in an isoosmotic solution, they excrete solutes to make the concentration of solutes in the water equal to the concentration of solutes in their cells.

	such as the tardigrade is lethal
	is a problem because carbohydrates are fragile and break down when they dry out
	has nothing in common with freezing
	is a problem because fluid-mosaic cell membranes fall apart when deprived of water
	may be less damaging in the presence of sugar

	drug use
	consumption of foods high in nitrates, such as green vegetables
	protein metabolism
	the body's attempts to maintain pH homeostasis
	metabolism of fatty foods

	They have different diets.
	Land animals can get the energy needed to make urea or uric acid.
	Ammonia is very toxic, and it takes lots of water to dilute it.
	Land animals cannot afford the energy needed to make ammonia.
	Fish need to get rid of ammonia, but land animals need it to live.

	uric acid
	amino acids
	ammonia
	urea
	nitrite

	ammonia because it uses less energy to make than uric acid or urea
	urea because it is less toxic than uric acid
	uric acid because it takes less energy to make than urea
	uric acid because it does not require water for excretion
	ammonia because it is the most soluble of all the nitrogen-containing metabolic waste products

	is synthesized in the kidneys from ammonia and CO2
	forms solids that are relatively insoluble and nontoxic
	readily decomposes on exposure to air
	is readily excreted through feathers and scales
	can be recycled and utilized as an additional energy source

	elimination of nitrogenous wastes
	maintenance of salt balance
	elimination of undigested foods
	maintenance of the water balance
	production of urine

	water
	red blood cells
	H+ ions
	amino acids
	urea

	filtration and secretion
	reabsorption and secretion
	reabsorption and excretion
	filtration and reabsorption
	secretion and excretion

	insects .... excretion
	annelids ... excretion and osmoregulation
	bats ... osmoregulation
	earthworms ... excretion
	birds ... Hormones and the Endocrine System

	the breakdown of body wastes
	the excretion of wastes
	the regulation of body fluid composition
	filtration of the blood
	production of urine

	loop of Henle
	ureter
	urethra
	uvula
	none of the above

	neurons
	glomeruli
	ureters
	nephrons
	collecting ducts

	Bowman's capsule
	collecting duct
	glomerulus
	loop of Henle
	proximal convoluted tubule

	filter the blood and capture the filtrate
	reabsorb water into the blood
	break down harmful toxins and poisons
	reabsorb salts and nutrients
	refine and concentrate the urine for excretion

	filtration of plasma
	reabsorption of water into the blood
	breakdown of harmful toxins and poisons
	reabsorption of salts and nutrients
	production and release of ADH

	blood capillaries
	urine
	lymphatic fluid
	cells of the kidney
	the loop of Henle

	water
	plasma proteins
	urea
	glucose
	sodium

	Bowman's capsule is a network of capillaries inside the glomerulus.
	The proximal tubule is the portion of the nephron tubule farthest from Bowman's capsule.
	The renal cortex, which contains the nephrons, is interior to the renal medulla.
	The loop of Henle is located between the proximal tubule and the distal tubule.
	The distal tubule of a nephron connects with the renal pelvis of the kidney via the ureter.

	The renal artery and the renal vein form the line of demarcation between the renal cortex, and the renal medulla.
	There are two capillary beds in each nephron.
	A collecting duct receives filtrate from only one nephron.
	The ureter drains the kidney; the urethra drains the bladder.
	The renal artery brings metabolic waste to the kidney while the renal vein takes filtered blood from the kidney.

	Filtration happens when blood pressure forces water, nitrogenous waste, and valuable solutes from the blood into the nephron's proximal tubule.
	Reabsorption is the reclamation process that returns valuable solutes and water to the capillaries from the nephron so they are not wasted in the urine.
	Secretion transports certain toxins, drugs, and excessive ions from the capillaries to the filtrate.
	Excretion moves urine, the processed filtrate, out of the kidney, through the ureter, the bladder, and finally out of the body via the urethra.
	Reabsorption is the process where toxins, drugs, and excessive ions that remain in the blood after filtration are transported into the nephron for disposal in the urine.

	tubular secretion
	capsular filtration
	blood cell formation
	cellular respiration
	selective reabsorption

	excrete the maximum amount of salt
	neutralize toxins that might accumulate in the kidney
	control the pH of the interstitial fluid
	excrete a large amount of water
	establish a hyperosmotic interstitial medullary concentration

	It provides water for reabsorption by the interstitial fluid and capillaries.
	It loses urea to the renal medulla, helping this tissue to maintain its concentration gradient of solutes.
	It absorbs some drugs and poisons from surrounding capillaries.
	It helps maintain the concentration gradient of NaCl in the interstitial fluid, thus increasing water reabsorption.
	It collects processed filtrate from the nephrons.

	Bowman's capsule and the proximal tubule
	the descending limb of the loop of Henle
	the loop of Henle
	the thick segment of the ascending limb and the distal tubule
	the collecting duct

	Water will diffuse into the nephron by osmosis.
	Water will be pumped into the nephron by active transport.
	Water will diffuse out of the nephron by osmosis.
	Water will be pumped out of the nephron by active transport.
	There will be no net movement of water.

	During times of increased solute concentrations, ADH causes nephrons to absorb water faster.
	During times of higher solute concentrations, ADH causes more water to be released from the nephrons to be reabsorbed by the blood.
	Low levels or the absence of ADH in the blood are the brain's response to thirst.
	ADH is the only hormone that provides a system of control over the kidney as an osmoregulator for urine production.
	ADH controls the rate that filtrate moves from the glomerulus into Bowman's capsule.

	thyroid gland ... low blood sugar ... kidney blood vessels to constrict
	pituitary gland ... low blood osmolarity ... decreased permeability to water of a kidney's collecting duct
	adrenal gland ... high blood osmolarity ... increased permeability to water of a collecting duct
	pituitary gland ... high blood osmolarity ... increased permeability to water of a collecting duct
	adrenal gland ... low blood pressure ... increased water and solute reabsorption at the proximal tubule of the kidney

	enhances aldosterone production
	inhibits aldosterone production
	causes cellular metabolism to proceed at a faster rate
	enhances ADH (vasopressin) production and release
	inhibits ADH (vasopressin) production and release

	an increase in blood pressure or blood volume within the heart
	an increase in the solute concentration of the blood plasma
	a decrease in the solute concentration of the blood plasma
	a decrease in the blood pressure or blood volume in the afferent arteriole
	consumption of alcohol

	kangaroo rat is adapted to living in an environment where water is scarce
	white rat's diet is much less varied than the kangaroo rat's diet
	kangaroo rat cannot always find food
	kangaroo rat produces more body wastes
	kangaroo rat has less stress and lower blood pressure