In gymnosperms, microspore develops into a male gametophytic generation which is highly reduced and is confined to only a limited number of cells. This reduced gametophyte is known as

Options

A. Pollen grain
B. Endosperm
C. Prothallus
D. Embryo sac

Answer

To solve the question regarding the reduced male gametophyte in gymnosperms, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Gymnosperms**:
- Gymnosperms are a group of seed-producing plants that include conifers, cycads, Ginkgo, and gnetophytes. They are characterized by having seeds that are not enclosed in an ovary (hence the term "naked seeds").

2. **Microspore Development**:
- In gymnosperms, the microspore is produced through meiosis in the microsporangia. This microspore is crucial as it develops into the male gametophyte.

3. **Male Gametophyte Characteristics**:
- The male gametophyte in gymnosperms is highly reduced and consists of only a limited number of cells. This is a significant characteristic that distinguishes it from other plant groups.

4. **Identification of the Reduced Gametophyte**:
- The reduced male gametophyte that develops from the microspore is known as the **pollen grain**. This pollen grain is responsible for the transfer of male gametes (sperm cells) during fertilization.

5. **Exclusion of Other Options**:
- The other options provided (Endosperm, Prothallus, and Embryo Sac) do not fit the description of the reduced male gametophyte in gymnosperms:
- **Endosperm**: A tissue that nourishes the developing embryo, primarily found in angiosperms.
- **Prothallus**: The gametophyte stage in pteridophytes (ferns).
- **Embryo Sac**: The female gametophyte in angiosperms.

6. **Conclusion**:
- Therefore, the correct answer to the question is that the reduced male gametophyte in gymnosperms is known as the **pollen grain**.

### Final Answer:
The reduced male gametophyte in gymnosperms is known as **pollen grain**.

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