Respiration without a distinct respiratory organ occurs in

Options

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

Answer

To solve the question "Respiration without a distinct respiratory organ occurs in:", we need to analyze each of the given options to determine which organism does not have a specialized respiratory organ.

### Step-by-Step Solution:

1. **Understand the Concept of Respiration**:
- Respiration is the process by which organisms exchange gases (oxygen and carbon dioxide) with their environment. Some organisms have specialized respiratory organs, while others do not.

2. **Analyze the Options**:
- **Fish**: Fish have gills, which are specialized organs for respiration in aquatic environments. Therefore, fish do not fit the criteria of respiration without a distinct respiratory organ.
- **Cockroach**: Cockroaches have spiracles, which are openings that lead to a network of tracheae for gas exchange. This means cockroaches also do not fit the criteria.
- **Tadpole**: Tadpoles, which are the larval stage of frogs, have gills for respiration while they are in the water. Thus, they also have a distinct respiratory organ.
- **Earthworm**: Earthworms do not have any specialized respiratory organs. Instead, they respire through their moist skin, where gas exchange occurs directly with the environment. Oxygen is absorbed through the skin and transported by hemoglobin dissolved in their blood plasma, while carbon dioxide is released.

3. **Conclusion**:
- Based on the analysis, the organism that performs respiration without a distinct respiratory organ is the **earthworm**.

### Final Answer:
The correct answer is **earthworm**.

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