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In gymnosperms, the microspores develop ...

In gymnosperms, the microspores develop into a male gametophytic generation which is
1 highly developed and is made of large number of cells
2 semi- / parasitic
3 free living
4 highly reduced and is confined to only a limited number of cells.

A

highly developed and is made of large number of cells

B

semi-`//` parasitic

C

free living

D

highly reduced and is confined to only a limited number of cells.

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To solve the question regarding the male gametophytic generation in gymnosperms, we can follow these steps: ### Step-by-Step Solution: 1. **Understanding Gymnosperms**: - Gymnosperms are a group of seed-producing plants that have seeds that are not enclosed in an ovary (naked seeds). They produce cones which contain the reproductive structures. **Hint**: Recall that gymnosperms include conifers and that their seeds are exposed. 2. **Microspores in Gymnosperms**: - Microspores are produced in the microsporangia found in the male cones (microsporophylls). These microspores are haploid. **Hint**: Remember that microspores are the precursor to male gametophytes. 3. **Development of Male Gametophyte**: - The haploid microspores develop into male gametophytes. In gymnosperms, this male gametophyte is highly reduced compared to those in other plant groups. **Hint**: Think about how the male gametophyte functions in reproduction and its size relative to other plant structures. 4. **Characteristics of Male Gametophyte**: - The male gametophyte in gymnosperms is not highly developed; instead, it is confined to a limited number of cells. This reduced structure is what we refer to as the pollen grain. **Hint**: Consider what "highly reduced" means in terms of cell number and structure. 5. **Evaluating the Options**: - **Option 1**: Highly developed and made of a large number of cells - **Incorrect**. - **Option 2**: Semi-parasitic - **Incorrect**. - **Option 3**: Free living - **Incorrect**. - **Option 4**: Highly reduced and confined to a limited number of cells - **Correct**. **Hint**: Cross-reference the characteristics of the male gametophyte with the provided options. ### Conclusion: The correct answer is **Option 4: Highly reduced and is confined to only a limited number of cells**.
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