| 1. | Phagocytosis of bacteria |
| 2. | Secretion of heparin and histamine during inflammatory reactions |
| 3. | Destruction of parasites and involvement in allergic reactions |
| 4. | Transport of gases like oxygen and carbon dioxide |
| Type of Circulation | Characteristics | ||
| A. | Pulmonary Circulation | 1. | Carries oxygenated blood from the heart to tissues |
| B. | Systemic Circulation | 2. | Carries deoxygenated blood to the lungs for oxygenation |
| C. | Hepatic Portal System | 3. | Direct blood flow from digestive organs to liver |
| D. | Coronary Circulation | 4. | Supplies blood to the cardiac muscles |
| 1. | Increase heart rate and cardiac output. |
| 2. | Decrease heart rate and cardiac output. |
| 3. | Increase action potential conduction speed. |
| 4. | Increase the strength of ventricular contraction. |

| 1. | Blood is circulated more quickly, more precisely and at higher pressure to the organs. |
| 2. | Blood directly bathes the tissues, facilitating faster diffusion of gases. |
| 3. | Nutrients and waste are exchanged more efficiently in open spaces. |
| 4. | The heart does not require chambers for efficient circulation. |
| Statement I: | Fishes possess a two-chambered heart with an atrium and a ventricle, where deoxygenated blood is pumped to the gills for oxygenation. |
| Statement II: | Birds and mammals possess a four-chambered heart, which ensures complete separation of oxygenated and deoxygenated blood. |
| 1. | Both Statement I and Statement II are correct. |
| 2. | Statement I is correct but Statement II is incorrect. |
| 3. | Statement I is incorrect but Statement II is correct. |
| 4. | Both Statement I and Statement II are incorrect. |
| Assertion (A): | The sino-atrial node (SAN) is also known as the pacemaker of the heart. |
| Reason (R): | The SAN can generate action potentials at the highest frequency and initiate the heartbeat. |
| 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. |
| 1. | Heart failure refers to the heart’s inability to pump sufficient blood, while cardiac arrest is when the heart stops beating entirely. |
| 2. | Heart failure only affects the ventricles, whereas cardiac arrest affects the atria. |
| 3. | Heart failure is reversible, while cardiac arrest is not. |
| 4. | Cardiac arrest is caused by hypertension, while heart failure is caused by valve malfunction. |
| Oxygenated Blood | Deoxygenated Blood | |||
| 1. | Left atrium | Left ventricle | Right atrium | Right ventricle |
| 2. | Left atrium | Right atrium | Left ventricle | Right ventricle |
| 3. | Left atrium | Right ventricle | Right atrium | Right ventricle |
| 4. | Right atrium | Right ventricle | Left atrium | Left ventricle |
| 5. | Left ventricle | Right atrium | Left atrium | Right ventricle |