| Assertion (A): | Na+ reabsorption from glomerular filtrate occurs in PCT, ascending limb of loop of Henle and collecting duct |
| Reason (R): | Na+ is always reabsorbed by passive process in PCT, ascending limb of loop of Henle and collecting duct |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
| Assertion (A): | Vasa recta and Henle's loop play a significant role in maintaining high osmolarity of medullary interstitial fluid |
| Reason (R): | Osmolarity increases from 300 mOsmolL-1 to 1200 mOsmolL-1 as we move from cortex to medullary region |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
| I: | is a fine capillary network around the renal tubule formed by efferent arteriole. |
| II: | runs parallel to the Henle’s loop in juxtamedullary nephrons. |
| III: | is absent or highly reduced in cortical nephrons. |
| Assertion (A): | Ascending limb of the loop of Henle is impermeable to water and allows transport of electrolytes actively or passively. |
| Reason (R): | Dilution of filtrate takes place due to efflux of electrolytes in the medullary fluid |
| 1. | (A) is True, (R) is False |
| 2. | (A) is False, (R) is True |
| 3. | Both (A) and (R) are True and (R) is the correct explanation of (A) |
| 4. | Both (A) and (R) are True but (R) is not the correct explanation of (A) |
| Assertion (A): | The ascending limb of loop of Henle is also called the diluting segment of the nephron. |
| Reason (R): | In the ascending portion, the loop becomes impermeable to water and the cells of the loop actively reabsorb solutes from the luminal fluid. |
| 1. | (A) is True but (R) is False. |
| 2. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 3. | (A) is False but (R) is True. |
| 4. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| Assertion (A): | An excess of aldosterone can cause a decrease in potassium ion concentration in body fluids. |
| Reason (R): | Aldosterone acts mainly at the renal tubules and stimulates the reabsorption of Na+ and water. |
| 1. | Both (A) and (R) are True but (R) does not correctly explain (A). |
| 2. | (A) is True but (R) is False. |
| 3. | Both (A) and (R) are False. |
| 4. | Both (A) and (R) are True and (R) correctly explains (A). |
| I: | They are located at the level of T12 – L2-L3 vertebrae |
| II: | Left kidney is slightly lower placed than the right kidney |
| I: | Cartilaginous fishes are ammonotelic. |
| II: | Mammals are ureotelic. |
| III: | Land snails are uricotelic. |
| Assertion (A): | Atrial Natriuretic Factor (ANF) mechanism acts as a check on the renin-angiotensin mechanism. |
| Reason (R): | An increase in blood flow to the atria of the heart can cause the release of ANF. |
| 1. | Both (A) and (R) are True and (R) correctly explains (A). |
| 2. | Both (A) and (R) are True but (R) does not correctly explain (A). |
| 3. | (A) is True; (R) is False. |
| 4. | Both (A) and (R) are False. |
| I: | Each kidney of an adult human measures 10-12 cm in length, 5-7 cm in width and 2-3 cm in thickness. |
| II: | The DCTs of many nephrons open into a straight tube called collecting duct. |
| III: | Each nephron has two parts – the glomerulus and the renal tubule. |
| IV: | The renal tubule begins with the proximal convoluted tubule. |
| 1. | Only I and II | 2. | Only I, II and III |
| 3. | Only II and III | 4. | I, II, III and IV |