physiology questions

Question 1

which nephron structure is especially important in the kidneys ability to produce urine of varying concentrations?

Answer 1

loop of Henle

Question 2

what is the glomerular filtrate?

Answer 2

-a protein free plasma that is formed as a result of passive forces acting across the glomerular membrane

Question 3

which factor would reduce the net filtration pressure the most:

1. A large increase in blood colloid osmotic pressure
2. A low capsular hydrostatic pressure
3. Vasodilation of the afferent arteriole
4. Vasoconstriction of the efferent arteriole
5. A high glomerular hydrostatic pressure

Answer 3

1- A large increase in blood colloid osmotic pressure

Question 4

When arteriole BP is elevated above normal, which of the following compensatory changes in renal function occur as a result of the baroreceptor reflex?

1. Afferent arteriole vasoconstriction and reduction in GFR
2. Reduction in GFR
3. Afferent arteriole vasoconstriction
4. Afferent arteriole vasodilation
5. All of the above

Answer 4

4- Afferent arteriole vasodilation

Question 5

what is the renal threshold?

Answer 5

-plasma concentration of a particular substance which its Tm is reaches and the substance first appears in urine

Question 6

Role of aldosterone?

Answer 6

-stimulates Na+ reabsorption in the distal and collecting tubules and stimulates K+ secretion in distal tubule

Question 7

what is plasma clearance?

Answer 7

-the volume of plasma that is completely cleared of a substance by the kidneys in one minute of time

Question 8

what establishes the medullary vertical osmotic gradient by means of counter current multiplication?

Answer 8

Loop of Henle