Heart pumps only impure blood in case of

Options

A. Shark
B. Whale
C. Frog
D. Lizard

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which organism has a heart that pumps only impure blood. This means we need to identify an organism where the heart does not mix oxygenated blood with deoxygenated blood.

2. **Identifying Organisms**: The organisms mentioned include sharks, whales, frogs, and lizards. We need to analyze the heart structure of each to determine which one fits the criteria.

3. **Analyzing Shark's Heart**: Sharks are classified as cartilaginous fish and possess a two-chambered heart. This heart consists of one atrium and one ventricle.

4. **Blood Flow in Sharks**: In sharks, the blood that returns from the body is impure (deoxygenated) and enters the heart. This impure blood is then pumped directly to the gills where it gets oxygenated. The heart does not mix this impure blood with oxygenated blood, which is a unique characteristic of sharks.

5. **Comparing Other Organisms**:
- **Whales**: As mammals, they have a four-chambered heart that separates oxygenated and deoxygenated blood.
- **Frogs**: They have a three-chambered heart, which allows some mixing of oxygenated and deoxygenated blood.
- **Lizards**: Similar to frogs, lizards also have a three-chambered heart.

6. **Conclusion**: Based on the analysis, the only organism that pumps only impure blood through its heart is the shark. Therefore, the correct answer is the shark.

**Final Answer**: The heart pumps only impure blood in the case of the shark.

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