In bryophytes

Options

A. Both generations are independent
B. Gametophytes are dependent upon sporophytes
C. Sporophytes complete their life cycle
D. Sporophytes are dependent upon gametophytes

Answer

**Step-by-Step Solution:**

1. **Understanding Bryophytes**: Bryophytes are a group of non-vascular plants that include mosses, liverworts, and hornworts. They exhibit a life cycle that alternates between two generations: the gametophyte and the sporophyte.

2. **Identifying the Generations**: In bryophytes, the dominant generation is the gametophyte, which is typically green, leafy, and photosynthetic. The sporophyte generation is usually smaller, dependent on the gametophyte for nutrition, and often consists of a stalk and a capsule where spores are produced.

3. **Dependency of Generations**: The key characteristic of bryophytes is that the sporophyte is dependent on the gametophyte. This means that the sporophyte cannot survive independently and relies on the gametophyte for its sustenance.

4. **Analyzing the Options**:
- The first option states that both generations are independent, which is incorrect.
- The second option suggests that gametophytes are independent of sporophytes, which is true.
- The third option mentions that sporophytes complete their life cycle, which is misleading since they are dependent on gametophytes.
- The fourth option states that sporophytes are dependent upon gametophytes, which is correct.

5. **Conclusion**: Based on the understanding of the life cycle of bryophytes and the dependency relationship between the gametophyte and sporophyte, the correct answer is that sporophytes are dependent upon gametophytes.

**Final Answer**: The correct option is that sporophytes are dependent upon gametophytes.

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