A patch of nodal tissue responsible for initiating the rhythmic contractile activity of heart is present in

Options

A. Lower left corner of the left ventricle
B. Upper right corner of the right atrium
C. Lower left corner of the right ventricle
D. Upper left corner of the left atrium

Answer

To solve the question, "A patch of nodal tissue responsible for initiating the rhythmic contractile activity of heart is present in," we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Nodal Tissue**: The question refers to a specific type of nodal tissue in the heart that initiates rhythmic contractions. This tissue is known as the sinoatrial node (SA node).

2. **Understand the Function of the SA Node**: The SA node is often referred to as the "pacemaker" of the heart because it generates electrical impulses that trigger heartbeats, thereby controlling the heart's rhythm.

3. **Locate the SA Node**: The SA node is located in the upper right corner of the right atrium. This anatomical position is crucial for its function in coordinating the heart's contractions.

4. **Evaluate the Options**: The question provides several options regarding the location of the SA node:
- Lower left corner of the left ventricle
- Upper right corner of the right atrium
- Lower left corner of the right ventricle
- Upper left corner of the right atrium

5. **Select the Correct Answer**: Based on our understanding, the correct answer is the "upper right corner of the right atrium," as this is where the SA node is located.

### Final Answer:
The patch of nodal tissue responsible for initiating the rhythmic contractile activity of the heart is present in the **upper right corner of the right atrium**.

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