In some plants such as Rhizophora growing in swampy areas, many roots come out of the ground and grow vertically upwards. Such roots and called

Options

A. Pneumatophores
B. Prop roots
C. Stilt roots
D. none of the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Environment**: Recognize that Rhizophora is a plant that grows in swampy areas where waterlogged conditions limit the availability of oxygen in the soil.

2. **Identifying the Problem**: In swampy areas, plants face difficulty in obtaining oxygen from the water due to the lack of dissolved oxygen. This necessitates an adaptation for survival.

3. **Root Modifications**: To cope with the low oxygen levels, some plants develop specialized roots that can access atmospheric oxygen. These roots emerge above the ground.

4. **Naming the Roots**: The roots that grow vertically upwards from the ground in such plants are known as **aerial roots**. In the case of Rhizophora, these specific aerial roots are called **nematophores**.

5. **Function of Nematophores**: Nematophores serve the primary function of extracting atmospheric oxygen, which is essential for the plant's respiration, especially when the oxygen in the water is insufficient.

6. **Conclusion**: Therefore, the roots that come out of the ground and grow vertically upwards in Rhizophora are referred to as **nematophores**.

**Final Answer**: Nematophores

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