Collecting duct does not:
I: | allow reabsorption of large amount of water during concentration of urine. |
II: | allow passage of small amounts of urea into medullary interstitium to keep up the osmolarity. |
III: | play a role in the maintenance of pH and ionic balance of blood by the selective secretion of H+ and K+ ions. |
1. | Only I and II | 2. | Only III |
3. | Only II | 4. | I, II and III are incorrect |
The region of human kidney where you expect to find maximum osmolarity is:
1. at the top of the renal cortex
2. at the bottom of the renal cortex
3. at the top of the renal medulla
4. at the bottom of the renal medulla
The urine concentrating ability of mammals and birds is correlated with the length of their:
1. | ureters | 2. | proximal convoluted tubules |
3. | distal convoluted tubules | 4. | loops of Henle |
1. | 1200, 300 | 2. | 300, 1200 |
3. | 300, 600 | 4. | 600, 300 |
I: | A is NaCl which is transported by the ascending limb of Henle’s loop, exchanged with the ascending limb of vasa recta and returned to the interstitium by the descending portion of vasa recta. |
II: | B is urea which enters the thin segment of the ascending limb of Henle’s loop and is transported back to the interstitium by the collecting tubule. |
III: | C is water. |
1. | Only I and II | 2. | Only II and III |
3. | Only I and III | 4. | I, II and III |
Aldosterone can be secreted by adrenal cortex when it is stimulated most directly by:
1. ADH | 2. Renin |
3. Angiotensin | 4. ANF |
What acts as a check on the renin-angiotensin mechanism?
1. | ANF | 2. | ADH |
3. | Aldosterone | 4. | Erythropoietin |
JG cells can be activated to release renin by all the following except:
1. A fall in glomerular blood flow
2. A fall in glomerular blood pressure
3. An increase in venous return to the heart
4. A fall in GFR