| (a) | The cortex extends in between the medullary pyramids as calyx. |
| (b) | Vasa recta is absent or highly reduced in cortical nephrons. |
| (c) | Kidney is situated between the levels of the 12th thoracic and 3rd lumbar vertebra close to the dorsal inner wall of the abdominal cavity. |
| 1. | Kidneys are reddish brown, round-shaped structures situated between the levels of the last thoracic and third lumbar vertebra. |
| 2. | Kidneys are close to the dorsal inner wall of the abdominal cavity. |
| 3. | Each kidney of adult human measures 0.5 - 0.7 m in width, 0.2 – 0.3 m in thickness with an average weight of 120 – 150 g. |
| 4. | Towards the centre of the inner convex surface of the kidney is a notch called the hilum through which the ureter, blood vessels, and nerves pass. |
| Assertion (A): | ANF mechanism acts as a check on the renin-angiotensin mechanism. |
| Reason (R): | ANF can cause vasodilation (dilation of blood vessels) and thereby decrease blood pressure. |
| 1. | Both (A) and (R) are True and (R) correctly explains (A). |
| 2. | (A) is True but (R) is False. |
| 3. | Both (A) and (R) are False. |
| 4. | Both (A) and (R) are True but (R) does not correctly explain (A). |
| Statement I: | Protonephridia or flame cells are the excretory structures in Aschelminthes. |
| Statement II: | Reptiles, birds, land snails, and insects are uricotelic animals. |