Where in the nephron does most solute reabsorption occur?
Proximal convoluted tubule
Approximately 80% of the energy used for active transport is devoted to the reabsorption of __________.
Sodium
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?
- water and small solutes
- blood cells and large particles
- ions, such as sodium and potassium
nitrogenous waste particles, such as
urea
Blood cells and large particles
What is the primary driving force (pressure) that produces glomerular filtration?
Hydrostatic pressure of blood (blood pressure)
Which of the following would only be found in the glomerular filtrate
if the glomerular membrane were damaged?
1. protein
2. chloride
3. creatinine
4. glucose
Protein
If the osmotic pressure in the glomerular capillaries increased from 28 mm Hg to 35 mm Hg, would net filtration increase or decrease?
Net filtration would decrease
Calculate the net filtration pressure if capillary hydrostatic pressure is 60 mm Hg, capillary osmotic pressure is 25 mm Hg, and capsular hydrostatic pressure is 10 mm Hg.
25 mm Hg
60 - (25 + 10) = 25 mm Hg
Most solutes that are reabsorbed in the proximal convoluted tubule
use which of the following pathways?
paracellular
OR
transcellular
Transcellular
During reabsorption of water in the proximal convoluted tubule, what
causes water to diffuse from the lumen into the interstitial space?
1. a decrease in the osmolarity of the
interstitium
2.
active transport of water
3. an increase in the osmolarity of the
interstitium
An increase in the osmolarity of the interstitium
The decreased intracellular concentration of sodium in tubular cells
during active transport is caused by which of the following mechanisms?
1. the sodium-potassium ATPase pump in the basolateral
membrane
2. the sodium-potassium ATPase pump in the luminal
membrane
3. sodium-glucose cotransporter
4. passive sodium channels
The sodium-potassium ATPase pump in the basolateral membrane
The active transport of which ion out of proximal convoluted tubule
cells causes the reabsorption of both water and solutes?
1. potassium
2. sodium
3. chloride
Sodium
Which of the following transporters in the luminal membrane results
in secretion?
1. Na+-H+ countertransport
2. Na+-glucose
cotransporter
3. potassium ion channel
4. glucose carrier transporter
Na+-H+ countertransport
What is the limiting factor for the reabsorption of most actively
transported solutes in the proximal tubule?
1. number of transport carriers in the basolateral
membrane
2. number of sodium-potassium ATPase pumps in the
basolateral membrane
3. number of transport carriers in the
luminal membrane
Number of transport carriers in the luminal membrane
Which of the following best describes glomerular filtration rate (GFR)?
1. the volume of filtrate created by the kidneys per
minute
2. the volume of urine leaving the kidneys per
minute
3. the volume of filtrate created at the glomerulus per
liter of blood flowing through the glomerular capillaries
4. the
volume of blood flowing through the glomerular capillaries per minute
The volume of filtrate created by the kidneys per minute
GFR regulation mechanisms primarily affect which of the following?
blood osmotic pressure (OPg)
capsular osmotic pressure
(OPc)
glomerular hydrostatic pressure (HPg)
capsular
hydrostatic pressure (HPc)
Glomerular hydrostatic pressure (HPg)
Which of the following are mechanisms of intrinsic control of
glomerular filtration (renal autoregulation)?
1. myogenic mechanism and tubuloglomerular feedback
2.
tubuloglomerular feedback and the renin-angiotensin mechanism
3.
sympathetic nervous system control and the renin-angiotensin
mechanism
4. myogenic mechanism and sympathetic nervous system control
Myogenic mechanism and tubuloglomerular feedback
Macula densa cells of the juxtaglomerular apparatus (JGA) regulate
GFR through which intrinsic mechanism?
1. myogenic mechanism
2. renin-angiotensin
mechanism
3. sympathetic nervous system control
4.
tubuloglomerular feedback
Tubuloglomerular feedback
The myogenic mechanism of renal autoregulation primarily involves
smooth muscle in which blood vessels?
1. afferent arterioles
2. systemic arterioles
3.
efferent arterioles
4. glomeruli
Afferent arterioles
What does a high concentration of NaCl in the renal tubule at the
juxtaglomerular apparatus (JGA) most likely indicate?
1. insufficient NaCl reabsorption due to low GFR
2.
excessive NaCl reabsorption due to low GFR
3. insufficient NaCl
reabsorption due to high GFR
4. excessive NaCl reabsorption due
to high GFR
Insufficient NaCl reabsorption due to high GFR
Through the tubuloglomerular feedback mechanism, how would an
increase in filtrate NaCl concentration affect afferent arteriole diameter?
1. Afferent arteriole diameter would increase.
2. Afferent
arteriole diameter would stay about the same.
3. Afferent
arteriole diameter would decrease.
Afferent arteriole diameter would decrease.
Granular cells of the juxtaglomerular apparatus (JGA) regulate GFR
through which mechanism?
1. renin-angiotensin mechanism
2. tubuloglomerular feedback
mechanism
3. sympathetic nervous system controls
4. myogenic mechanism
Renin-angiotensin mechanism
Which hormone(s) is/are required for facultative water reabsorption in the collecting ducts?
ADH
A nonfasting 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?
1. The individual exceeded the transport maximum.
2. The
individual is glucose intolerant.
3. The individual has diabetes
mellitus.
4. Some glucose is always present in the urine.
The individual exceeded the transport maximum
Which part of the brain controls the micturition reflex?
Pons
The __________ keeps the urethra closed when urine is not being passed from the bladder and prevents leaking between voiding.
internal urethral sphincter
Who is awesome?
- Alex
- Iffy
- Terra
Terra
Since most patients with renal failure produce little or no urine,
hemodialysis often involves removal of water from the blood. However,
side-effects may develop if too much fluid is removed from the blood.
Which of the following is NOT one of the potential side-effects?
1. dizziness
2. vasoconstriction of afferent
arterioles
3. low blood pressure
4. muscle fatigue
Vasoconstriction of afferent arterioles
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