Heart of fishes `:-`

Options

A. Two chambered
B. Venous heart
C. Both (1) `&` (2)
D. None of the above

Answer

### Step-by-Step Solution:

1. **Understanding the Heart Structure in Fishes**:
- The heart of fishes is classified as a **two-chambered heart**. This means it consists of two main parts: an **auricle** (or atrium) and a **ventricle**.

2. **Identifying the Type of Blood**:
- The heart of fishes is referred to as a **venous heart** because it primarily contains **deoxygenated blood**. This is the blood that has returned from the body tissues and is low in oxygen.

3. **Blood Flow Process**:
- The deoxygenated blood from the body enters the **auricle**.
- From the auricle, the blood moves into the **ventricle**.
- The ventricle then pumps this deoxygenated blood to the **gills**.

4. **Oxygenation of Blood**:
- In the gills, the blood gets oxygenated. This means it picks up oxygen from the water.
- The now oxygen-rich blood is then distributed to the rest of the body tissues.

5. **Cycle of Blood Flow**:
- After delivering oxygen to the tissues, the blood becomes deoxygenated again and returns to the auricle, completing the cycle.

6. **Conclusion**:
- Therefore, the heart of fishes is characterized as a **two-chambered venous heart**, which efficiently circulates blood through the body and gills.