Pacemaker of heart is

Options

A. AV node
B. SA node
C. SV node
D. tricuspid valve

Explanation

**Step-by-Step Solution:**

1. **Understanding the Heart's Functionality**: The heart is known as a myogenic heart, which means that it can generate its own impulses to contract and pump blood without needing external nervous stimuli.

2. **Identifying the Impulse Generation Center**: The primary center for generating these impulses is known as the sinoatrial (SA) node. This node is crucial for initiating the heartbeat.

3. **Location of the SA Node**: The SA node is located in the right atrium of the heart. Its strategic position allows it to effectively control the rhythm of the heart.

4. **Role of the SA Node**: Because the SA node generates impulses that trigger heartbeats, it is referred to as the "pacemaker" of the heart. This term signifies its role in setting the pace for the heart's rhythm.

5. **Comparison with Other Nodes**: While the atrioventricular (AV) node also plays a role in the conduction system of the heart, it does not initiate the heartbeat. Instead, it receives impulses from the SA node and transmits them to the ventricles. There is no such thing as an "SV node" in the context of heart pacing.

6. **Conclusion**: Therefore, the pacemaker of the heart is the SA node.

**Final Answer**: The pacemaker of the heart is the sinoatrial (SA) node.

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