Mark the incorrect statement about the body wall of earthworm

Options

A. Body wall is covered externally by a thin non-cellular cuticle
B. Below the cuticle epidermis is present which is made up of compound columnar epithelium
C. The epidermis contains secretory gland cells which produce mucus
D. Both circular and longitudinal muscles are present and an innermost lining of intersegmental grooves

Explanation

To determine the incorrect statement about the body wall of the earthworm, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding the Body Wall of Earthworm**:
- The body wall of an earthworm consists of several layers, including a cuticle, epidermis, and muscle layers.

2. **Analyzing the First Option**:
- The statement mentions that the body wall is covered externally by a thin non-cellular cuticle.
- **Evaluation**: This statement is correct. Earthworms do have a non-cellular cuticle that protects their body surface.

3. **Analyzing the Second Option**:
- This option states that below the cuticle, the epidermis is present, which is made up of compound polymer epithelium.
- **Evaluation**: This statement is incorrect. The epidermis of an earthworm is made up of simple columnar epithelium, not compound epithelium.

4. **Analyzing the Third Option**:
- The statement claims that the epidermis contains secretory glands that produce mucus.
- **Evaluation**: This statement is correct. The secretory glands in the epidermis do produce mucus, which aids in respiration and locomotion.

5. **Analyzing the Fourth Option**:
- This option states that both circular and longitudinal muscles are present in the innermost lining of the intersegmental grooves.
- **Evaluation**: This statement is also correct. Earthworms have both circular and longitudinal muscles that help in movement.

6. **Conclusion**:
- After evaluating all the options, the incorrect statement about the body wall of the earthworm is the second option, which incorrectly describes the type of epithelium present in the epidermis.

### Final Answer:
The incorrect statement about the body wall of the earthworm is: **The epidermis is made up of compound polymer epithelium.**

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