The atrium and ventricle of same side are separated by a thick fibrous tissue called the

Options

A. Inter-atrial septum
B. Inter-ventricular septum
C. Atrio-ventricular septum
D. Atrio-ventricular valve

Explanation

To answer the question regarding the thick fibrous tissue that separates the atrium and ventricle of the same side in the heart, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Chambers of the Heart**:
- The heart consists of four chambers: two atria (upper chambers) and two ventricles (lower chambers). The left atrium and left ventricle are on one side, while the right atrium and right ventricle are on the other side.

2. **Understand the Function of the Atria and Ventricles**:
- The atria receive blood returning to the heart, while the ventricles pump blood out of the heart. The separation of these chambers is crucial for the proper functioning of the heart.

3. **Recognize the Separation Mechanism**:
- The atria and ventricles on the same side are separated by a structure that prevents the mixing of blood between these chambers.

4. **Identify the Correct Term**:
- The thick fibrous tissue that separates the atrium and ventricle of the same side is known as the **Arterioventricular septum**.

5. **Eliminate Incorrect Options**:
- Option 1: Inter-arterial septum - Incorrect, as this refers to the separation between the two atria.
- Option 2: Inter-ventricular septum - Incorrect, as this refers to the separation between the two ventricles.
- Option 3: Arterioventricular septum - Correct, as it specifically refers to the separation between the atrium and ventricle on the same side.
- Option 4: Incorrect option - Not relevant.

### Final Answer:
The atrium and ventricle of the same side are separated by a thick fibrous tissue called the **Arterioventricular septum**.

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