Seed coat is not thin, membranous in

Options

A. Groundnut
B. Gram
C. Maize
D. Coconut

Answer

To determine which seed coat is not thin and membranous, we will analyze the seed coats of the given options: groundnut, gram, maize, and coconut.

### Step-by-Step Solution:

1. **Understanding Seed Coat**:
- The seed coat is the outer protective layer of a seed. It serves to protect the seed from physical damage, environmental factors, and pests. Additionally, it helps maintain the seed in a dormant state until conditions are favorable for germination.

2. **Evaluating Each Option**:
- **Groundnut**: The seed coat of groundnut is thin and membranous. Therefore, this option is incorrect.
- **Gram**: Similar to groundnut, the seed coat of gram is also thin and membranous. This option is also incorrect.
- **Maize**: The seed coat of maize is thin and membranous as well. Thus, this option is incorrect too.
- **Coconut**: The seed coat of coconut is thick and membranous. This means it is not thin, making this option correct.

3. **Conclusion**:
- The correct answer is **Coconut** (Option D), as its seed coat is not thin and membranous.

### Final Answer:
Coconut (Option D) is the seed whose coat is not thin and membranous.