The part of seed which grows and develops into root on germination is :

Options

A. cotyledon
B. plumule
C. follicle
D. radicle

Answer

To answer the question, "The part of seed which grows and develops into root on germination is:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Seed Structure**:
- A seed consists of several parts, including the cotyledon, plumule, and radicle. Each part has a specific role in the germination process.

2. **Identifying the Cotyledon**:
- The cotyledon is the part of the seed that stores food. While it is essential for the seed's nourishment during germination, it does not develop into the root.

3. **Identifying the Plumule**:
- The plumule is the part of the seed that develops into the shoot system (the stem and leaves) of the plant. It is important for the plant's growth above the soil but does not form the root.

4. **Identifying the Radicle**:
- The radicle is the part of the seed that develops into the root during germination. It is the first part of the seedling to emerge from the seed and grows downward into the soil.

5. **Conclusion**:
- Based on the functions of these parts, the correct answer to the question is the radicle, as it is the part that grows and develops into the root during the germination of a seed.

### Final Answer:
The part of the seed which grows and develops into root on germination is the **radicle**.

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