9th Evals 2018 - Renal Flashcards
GFR formula
GFR = Kf x ( Pg - Pb - Pig + Pib)
Kf
glomerular filtration coefficient
Pb
Bowman’s Capsule hydrostatic pressure
Pg
glomerular capillary hydrostatic pressure
Pi g
glomerular capillary colloid osmotic pressure
Ap
systemic arterial pressure
Re
efferent arteriolar resistance
Ra
afferent arteriolar resistance
decrease Re. due to constriction or dilation?
constriction
increase Ra
constriction
effect on GFR.
decrease in Kf
decrease in GFR
effect on GFR.
increase in Pb
decrease in GFR
effect on GFR.
decrease in Pg
decrease in GFR
effect on GFR.
decrease in Ap
decrease in Pg = decrease in GFR
effect on GFR.
decrease in Re
decrease in Pg = decrease in GFR
effect on GFR.
increase in Ra
decrease in Pg = decrease in GFR
At plasma concentration of glucose higher than occur at transport maximum (Tm), the
excretion rate of glucose increases with increasing plasma glucose concentrations
main driving force for water reabsorption by the proximal tubule epithelium
active reabsorption of sodium
site of major autoregulatory control in so far as GFR and renal plasma flow:
afferent arteriole
with autoregulation, fluctuations in systemic mean arterial pressure within range of 80 to 180 mmHg will result in
no significant change in either renal plasma flow or GFR
An increase in delivery of NaCl to the distal nephron is expected to decrease GFR because of the operation of
Tubuloglomerular feedback
renal clearance (of substance X)
The volume of plasma passing through the kidneys that has been totally cleared of Substance X in a given period of time
For a substance which is reabsorbed with a transport maximum (Tm), once this Tm is exceeded, the excretion of the substance
Parallels the rate of filtration of the substance
freely filtered;
not reabsorbed;
not secreted;
not metabolized by kidneys;
clearance=
equal to the GFR
freely filtered;
not reabsorbed;
SECRETED;
clearance=
GREATER THAN THE GFR
- Given a normal GFR of 125 ml/min, which of the following substances is being reabsorbed given their respective clearance rates?
a. Substance A with a clearance rate of 500ml/min b. Substance B with a clearance rate of 250ml/min
c. Substance C with a clearance rate of 125 ml/min
d. Substance D with a clearance rate of 75ml/min
D
.Tubular secretion is a process that
a. Is important in the regulation of Na+ balance
b. Is important in the regulation of plasma H+ concentration
c. Always occurs by active transport
d. Referstothemovementofsubstancesfromthetubularlumentothe
peritubular capillaries
B
increase in renal glucose threshold
reduction in GFR
greatest percentage of sodium reabsorption takes place in
proximal tubule
the antidiuretic hormone controls water reabsorption only in the
collecting tubule
responsible for the establishment of the vertical medullary osmotic gradient
Loop of Henle
not permeable to water even in the presence of ADH
ascending limb of the loop of Henle
so-called countercurrent exchange mechanism in the vasa recta causes the concentration of NaCl and urea in the renal medulla to
remain the same
ADH exerts its action on the kidneys by increasing
free-water reabsorption
- The fluid that flows through the tubule is
a. hypotonic as it leaves the thick ascending limb
b. hypertonic as moves through the hair pin bend
c. same osmolality as plasma at it leaves the proximal tubule d. described by all of the above
D
In the proximal tubule, the reabsorption of glucose, amino acids and other small solutes that accompany the reabsorption of Na+ is known as the
Na+-solute symport mechanism
The thin descending limb of the loop of Henle is similar to the proximal tubule in that both are
very permeable to water
The thin descending and thin ascending segments of the loop of Henle are similar in that both
do not actively transport solutes
Common property of the segments representing the distal nephron
active reabsorption of Na+
As the tubular fluid leaves the distal convoluted tubule and enters the connecting tubule, it is observed to have an osmolality that is
lower than that of plasma
A positive free-water clearance means that the
Urine is hypotonic in relation to plasma
greatest reduction in tubular fluid volume occurs in
proximal tubule
- Micturition is
a. Initiated by the parasympathetic division of the autonomic nervous system
b. Inhibited by the sympathetic division of the autonomic nervous system
c. Considered to be a reflex
d. All of the above are correct
D
Stimulation of the osmoreceptors in the hypothalamus would cause
ADH release from the pituitary
32.Drinking beer (a beverage with high ethanol content and inhibits vasopressin secretion) would be expected to cause excretion of a
large volume of dilute urine
33.Drinking which of the following would lead to the highest rate of ADH secretion? a. Two liters of distilled water
b. Two liters of seawater
c. Two liters of isotonic saline
d. Two liters of human blood plasma
e. None of the above, since drinking two liters of any liquid leads to inhibition
of ADH release
B
- In a patient with severe renal artery stenosis (narrowing), which of the following would be expected to be decreased below normal
a. Plasma renin concentration
b. Plasma angiotensin II concentration
c. Blood pressure (hydrostatic pressure) in the glomerular capillaries d. Resistance to blood flow in the efferent arteriole
e. Systemic arteriolar blood pressure
C
- Administration of Angiotensin Converting Enzyme inhibitor (ACE inhibitor) to a patient with severe renal artery stenosis might lead to acute renal failure by
a. Inhibiting renal tubule potassium reabsorption
b. Increasing renal resistance to blood flow
c. Causing plasma proteins to be excreted in the urine d. Causing systems arterial hypertension
e. Reducing glomerular filtration rate
E
- An increase in secretion of renin would be expected to have what effect on sodium excretion and potassium excretion in the urine?
a. Increase in Na excretion and increase in K excretion
b. Increase in Na excretion and decrease K excretion
c. Decrease in Na excretion and increase in K excretion d. Decrease in Na excretion and decrease in K excretion
e. Decrease in Na excretion but no effect on K excretion
C
- The appearance of large amounts of ammonium ions in the urine is characteristic of the renal response to
a. respiratory acidosis
b. respiratory alkalosis
c. acidosis resulting from renal disease
d. alkalosis resulting from gastric vomiting
A
- An individual hoping for an LSD “acid high” mistakenly gives himself an intravenous injection of hydrochloric acid. The responses of his body which attempt to compensate for this mistake include which of the following:
a. hyperventilation
b. decrease in the acid form of the blood fixed buffers c. increase in blood bicarbonate ion concentration
d. increase in urine bicarbonate ion excretion
e. decrease in urine ammonium ion excretion
A
- About 4 to 6 days after you place a normal person on a low-sodium diet, which of the following will be observed?
a. plasma renin and aldosterone are below normal
b. plasma renin and aldosterone are above normal
c. plasma sodium concentration is below normal d. urine sodium concentration is above normal
b
- An increase in the osmolality of the extracellular fluid will:
a. stimulate the volume and osmoreceptors, and stimulate ADH secretion
b. stimulate the volume and osmoreceptors, and inhibit ADH secretion
c. inhibit the volume and osmoreceptors, and stimulate ADH secretion
d. inhibit the volume and osmoreceptors, and inhibit ADH secretion
e. cause no change in ADH secretion
A
- Which of the following is NOT a function of the kidneys? a. regulation of extracellular volume
b. regulation of plasma glucose concentration c. regulation of arterial blood pressure
d. excretion of the end products of protein metabolism
e. excretion of foreign chemicals (e.g. pharmaceuticals, food additives, etc.)
B
- Subjects A and B are 70 kg men. Subject A drinks 2 L of distilled water,and subject B drinks 2 L of isotonic NaCl. As result of these ingestions,subject B will have a
a. greater change in intracellular fluid volume
b. higher positive free-water clearance
c. greater change in plasma osmolarity
d. higher urine osmolarity
e. higher urine flow rate
D
the physiologic compensation for respiratory alkalosis
metabolic acidosis
Henderson-Hasselback equation
Increase in pCO2 will decrease the pH
extracellular edema. Edema happens when there is a decrease in
serum albumin.
- Glomerular filtration rate is increased by increases in the following, EXCEPT:
a. Afferent arteriole diameter
b. Efferent arteriole diameter
c. Glomerular pressure
d. Blood pressure
B
- Glomerular filtration rate is “zero” at which of the following arteriolar diameter:
a. 0.3
b. 0.5
c. 0.55
d. 0.6
A
- The glomerular pressure when glomerular filtration rate becomes “zero”, is at: a. 60
b. 55
c. 50
d. less than 45
D
- As blood pressure increases from 70 to 100, which of the following is increased:
a. Glomerular pressure
b. Glomerular filtration rate
c. Urine volume
d. All of the above
D
- In the combined effects of arteriolar diameter and pressure, which parameter was affected by closure of the valve that lead to absence of urine formation:
a. Bloodpressure
b. Glomerularpressure
c. Glomerular filtration rate
d. All of the above
D
- Which of the following ions is included among the parameters in the experiment:
a. Sodium
b. Potassium
c. Chloride
d. Hydronium
B
- Addition of ADH was shown to affect the following parameters in renal function, EXCEPT :
a. Glucose concentration
b. Urine volume
c. Urine concentration
d. Concentration gradient
A
the following factors was shown to change the parameter “concentration gradient”:
ADH
the urine concentration when both aldosterone and ADH are added:
1200
relationship, if any, is shown between urine volume and urine concentration:
As urine volume increases, urine becomes diluted
