Human Anatomy & Physiology: Ch 25 Flashcards

Approximately 80% of the energy used for active transport is devoted
to the reabsorption of _____.


What is the juxtaglomerular apparatus?

a system that regulates the rate of filtrate formation and systemic
blood pressure

Which of the following substances is not normally found in
filtrate?A) ions, such as sodium and potassiumB) blood
cells and large particlesC) nitrogenous waste particles, such as
ureaD) water and small solutes

B. Blood cells and large particles

What is the primary driving force that produces glomerular filtration?

hydrostatic pressure of blood (blood pressure)

Which substance would be found in higher concentration if the
membrane were damaged?A) creatinineB) glucoseC)
proteinD) chloride

C. Protein

If the osmotic pressure in the glomerular capillaries increased from
28 mm Hg to 35 mm Hg, would net filtration increase or decrease?


Calculate the net filtration pressure if capillary hydrostatic
pressure = 60 mm Hg, capillary osmotic pressure =25 mm Hg, and
capsular hydrostatic pressure =10 mm Hg.

25 mm Hg

Which of the following best describes glomerular filtration rate
(GFR)?A) the volume of urine leaving the kidneys per
minuteB) the volume of filtrate created by the kidneys per
minuteC) the volume of filtrate created at the glomerulus per
liter of blood flowing through the glomerular capillariesD) the
volume of blood flowing through the glomerular capillaries per minute

B. the volume of filtrate created by the kidneys per minute

GFR regulation mechanisms primarily affect which of the
following?A) glomerular hydrostatic pressure (HPg)B) blood
osmotic pressure (OPg)C) capsular hydrostatic pressure
(HPc)D) capsular osmotic pressure (OPc)

A. glomerular hydrostatic pressure (HPg)

Macula densa cells of the juxtaglomerular apparatus (JGA) regulate
GFR through which intrinsic mechanism?

tubuloglomerular feedback

The myogenic mechanism of renal autoregulation primarily involves
smooth muscle in which blood vessels?

afferent arterioles

What does a high concentration of NaCl in the renal tubule at the
juxtaglomerular apparatus (JGA) most likely indicate?

insufficient NaCl reabsorption due to high GFR

Through the tubuloglomerular feedback mechanism, how would an
increase in filtrate NaCl concentration affect afferent arteriole diameter?

Afferent arteriole diameter would decrease.

Granular cells of the juxtaglomerular apparatus (JGA) regulate GFR
indirectly through which mechanism?

renin-angiotensin mechanism

A non-fasting urine sample from an individual who has previously
ingested donuts and a soft drink showed the presence of sugar
(glucose). Which of the following statement explains the presence of
the glucose in the urine?

The individual exceeded the transport maximum.

Which part of the brain controls the micturition reflex?


The frequency of cystitis in men is lower than in women because ______.

the male urethra is longer than the female urethra

Urinary incontinence may occur if a person has ______.

an overactive detrusor muscle

True or False
Urea is reabsorbed in the loop of Henle.


An increase in the permeability of the cells of the collecting tubule
to water is due to ________.

an increase in the production of ADH

True or False
Aldosterone is a hormone that causes the renal tubules to reclaim
sodium ions from the filtrate.


The kidneys are stimulated to produce renin ________.

by a decrease in the blood pressure

Which of the following is not reabsorbed by the proximal convoluted
tubule? A) Na+ B) K+ C) GlucoseD) Creatinine


The renal ___________ is continuous with the ureter.


Which gland sits atop each kidney?


The juxtaglomerular apparatus is responsible for ______

regulating the rate of filtrate formation and controlling systemic
blood pressure

True or False
The urethra contains an internal sphincter of smooth muscle.


True or False
The terminal portion of the urinary system is the urethra.


In response to increased levels of aldosterone, the kidneys produce ____________________.

Urine with a lower concentration of sodium ions

True or False
The ureter transports urine from the kidney to the urinary bladder.


The ability to concentrate urine depends on the functions of ____________________.

Loop of henle (or the collecting duct)

The glomerulus differs from other capillaries in the body in that it ________

is drained by an efferent arteriole

The descending limb of the loop of Henle contains ________.

fluid that becomes more concentrated as it moves down into the medulla

Urine passes through the ________.

pelvis of the kidney to ureter to bladder to urethra

Tubular reabsorption ________.

by active mechanisms usually involves movement against an electrical
and/or chemical gradient

Urea transport into the medullary collecting duct is enhanced by ________.


True or False
Urine is 95% water by volume.


True or False
The ascending limb of the loop of Henle is impermeable to sodium
chloride and actively transports water into the surrounding
interstitial fluids.