Ch 23 Urinary System

The ureters pass anterior to the bladder and enter it from below.

False

Albuminuria is a common sign of diabetes mellitus.

False

Diseases that affect the descending corticospinal tracts may limit inhibition of the sacral somatic motor neurons and thus could result in urinary incontinence.

True

Ethyl (drinking) alcohol stimulates the secretion of ADH, thereby reducing reabsorption by the collecting duct.

False

Parathyroid hormone increases phosphate excretion by the proximal convoluted tubule as well as promotes synthesis of calcitriol.

True

The countercurrent multiplier mechanism for water conservation was discovered by limiting studies to humans and thus hypothesizing how form determines function.

False

The thick segment of the nephron loop is impermeable to water.

True

Glomerular filtration occurs because glomerular oncotic pressure overrides glomerular blood pressure

False

Angiotensin-converting enzyme is found only in the kidneys and converts angiotensinogen to angiotensin I.

False

Cells in the cleft between the afferent and efferent arterioles and among capillaries of the glomerulus are known as mesangial cells.

True

Glomerular capillaries suffer little damage from hypertension because of the protective influence of the afferent arterioles.

False

The fenestrated endothelium of the capillary has pores small enough to exclude blood cells from the filtrate.

True

The most toxic of our metabolic wastes are nitrogenous wastes.

True

Which of the following is not an organ of the urinary system?

collecting duct

A patient enters a hospital after a motorcycle accident. He complains of mid-back pain. X-rays reveal both rib and pelvic fractures. His emergency room examination includes urinalysis. Which of the following findings from the urinalysis would most likely suggest trauma to the kidneys from the accident, but not to the urinary bladder?

albuminuria

The innermost connective tissue layer protecting the kidney and assisting in staving off infection is known

the fibrous capsule.

A single lobe of a kidney is comprised of

one pyramid and the overlying cortex.

A renal pyramid voids urine into

the minor calyx

Which of these correctly traces blood flow from the renal artery into the renal cortex?

segmental → interlobar → arcuate→ interlobular

The transition from an afferent arteriole to an efferent arteriole occurs in the

glomerulus.

Blood plasma is filtered in

the renal corpuscle

Which of these form the inner layer of the glomerular capsule and wrap around the capillaries of the glomerulus?

podocytes

All of the following are composed of cuboidal epithelium with the exception of

thin segment of nephritis loop

Which are primarily responsible for maintaining the salinity gradient of the renal medulla?

juxtamedullary nephrons

In the nephron, the fluid that immediately precedes urine is known as

tubular fluid.

Glucose and amino acids are reabsorbed from the glomerular filtrate by

the proximal convoluted tubule.

Which of the following would reduce the glomerular filtration rate?

vasoconstriction of the afferent arteriole

The mechanism of stabilizing the GFR based on the tendency of smooth muscle to contract when stretched is known as what?

the myogenic mechanism

In response to a drop in overall blood pressure, ___ stimulates constriction of the glomerular inlet and even greater constriction of the outlet.

angiotensin II

Assuming all other values are normal, calculate the net filtration pressure in a patient with a drop in capsular hydrostatic pressure to 8 mmHg.

20 mm Hg out

Renin hydrolyzes angiotensinogen released from the ________ to form angiotensin I.

liver

Because of the great deal of active transport that occurs here, the _________ of all the nephrons collectively account for about 6% of one’s daily resting ATP and caloric consumption.

proximal convoluted tubules

Proximal convoluted tubules are responsible for reabsorbing all of the following except

hydrogen ions.

Total saturation of protein transporters for a given solute in the renal tubules would result in

appearance of that solute in the urine.

Which of the following is a direct result of antidiuretic hormone?

decreased urine volume

Aldosterone acts on

the distal convoluted tubule

Atrial natriuretic peptide reduces blood volume and pressure by all of the following means except

inhibiting renin and aldosterone secretion.

Hypocalcemia stimulates

secretion of parathyroid hormone

Which renal structure is responsible for producing hypertonic urine by reabsorbing water while allowing metabolic wastes and NaCl to pass through?

collecting duct

The urine is most likely to be hypotonic when

the body’s water volume is high.

Which of the following does not contribute to water conservation?

diuretics

The countercurrent multiplier recaptures ______ and is based on fluid flowing in ______ direction in two adjacent tubules.

sodium; the opposite

The overall purpose of the countercurrent exchange system is

to supply nutrients and oxygen to the renal medulla.

Which of these induces renin secretion, constricts afferent arterioles, and reduces GFR, and urine volume?

norepinephrine

Normal urine from a healthy person can be expected to contain all of the following except

glucose

What is the term for the pigment responsible for the color of urine?

urochrome

The minimum daily output of urine to meet the definition of polyuria is

2.0 L.

Prior to chemical tests for glycosuria, clinicians checked for sweetness of the urine as a sign of

diabetes mellitus.

Loop diuretics reduce body water content by acting on

the countercurrent multiplier system.

A hospital patient produces 4 mL/min of urine with a urea concentration of 8 mg/mL. Venous blood draw reveals urea concentration of 0.4 mg/mL. What is the percentage of cleared urea from glomerular filtrate?

64%