Respiration without a distinct respiratory organ occurs in

Options

A. Cockroach
B. Frog
C. Earthworm
D. Fish

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for organisms that perform respiration without a distinct respiratory organ. This means we need to identify organisms that do not have specialized structures like lungs or gills for gas exchange.

2. **Analyzing the Options**:
- **Cockroach**: Cockroaches have a tracheal system, which is a network of tubes that transport air directly to their tissues. This means they have a distinct respiratory system. Therefore, this option is incorrect.

- **Frog**: Frogs have multiple ways to respire, including skin, lungs, and the buccopharyngeal cavity. Since they have lungs, they also possess distinct respiratory organs. Thus, this option is incorrect.

- **Earthworm**: Earthworms do not have specialized respiratory organs. They respire through their moist skin, allowing oxygen to diffuse directly into their bloodstream. This method of respiration does not involve any distinct respiratory organs, making this option correct.

- **Fish**: Fish possess gills, which are specialized organs for respiration in water. Therefore, this option is also incorrect.

3. **Conclusion**: After analyzing all the options, the only organism that performs respiration without a distinct respiratory organ is the earthworm.

**Final Answer**: Respiration without a distinct respiratory organ occurs in earthworm.

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