Single circuit type of heart is found in

Options

A. Fish
B. Frog
C. Man
D. Limpet

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which organism has a single-circuit type of heart. This means we need to identify an organism whose heart circulates blood in a single loop.

2. **Analyzing the Options**: The options provided are:
- 1. Fish
- 2. Frog
- 3. Man
- 4. Limpet

3. **Evaluating Each Option**:
- **Option 1: Fish** - Fish have a two-chambered heart consisting of one atrium and one ventricle. The heart pumps deoxygenated blood to the gills where it gets oxygenated, and then the oxygenated blood is distributed to the body. This represents a single circuit of blood flow.
- **Option 2: Frog** - Frogs have a three-chambered heart (two atria and one ventricle). This allows for some mixing of oxygenated and deoxygenated blood, indicating a double circuit of blood flow.
- **Option 3: Man** - Humans have a four-chambered heart (two atria and two ventricles), which is also a double circuit system, separating oxygenated and deoxygenated blood.
- **Option 4: Limpet** - Limpets, being mollusks, also do not have a single-circuit heart. They typically have a heart that is more complex than that of fish.

4. **Conclusion**: Based on the analysis, the organism with a single-circuit type of heart is **Fish** (Option 1).

**Final Answer**: The single circuit type of heart is found in **Fish**.

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