| List-I | List-II | ||
| A. | P wave | I. | Heart muscles are electrically silent |
| B. | QRS complex | II. | Depolarization of ventricles. |
| C. | T wave | III. | Depolarization of atria. |
| D. | T-P gap | IV. | Repolarization of ventricles. |
| 1. | A-III, B-II, C-IV, D-I |
| 2. | A-II, B-III, C-I, D-IV |
| 3. | A-IV, B-II, C-I, D-III |
| 4. | A-I, B-III, C-IV, D-II |
| List-I | List-II | ||
| A. | Tricuspid valves | I. | Guards the opening between right atrium and right ventricle |
| B. | Sino-atrial node | II. | Guards the opening between the left atrium and the left ventricle |
| C. | Mitral valves | III. | Guards the opening of right and left ventricles into pulmonary artery and aorta, respectively |
| D. | Semilunar valves | IV. | Cardiac musculature in the right upper corner of right atrium |
| 1. | A-III, B-IV, C-II, D-I | 2. | A-II, B-I, C-IV, D-III |
| 3. | A-III, B-IV, C-I, D-II | 4. | A-I, B-IV, C-II, D-III |
Which one of the following animals has two separate circulatory pathways?
| 1. | Frog | 2. | Lizard |
| 3. | Whale | 4. | Shark |