In bryophytes, the dominant phase in the life cycle is the ____ plant body but in pteridophytes, the main plant body is_____.

Answer

**Step-by-Step Solution:**

1. **Understanding Bryophytes:**
- Bryophytes are non-vascular plants that include mosses, liverworts, and hornworts.
- In the life cycle of bryophytes, the dominant phase is the gametophyte stage.

2. **Defining Gametophyte:**
- The gametophyte is a multicellular haploid organism.
- "Haploid" means that it has a single set of chromosomes (n).
- The gametophyte develops from spores and produces haploid gametes.

3. **Role of Sporophyte in Bryophytes:**
- The sporophyte stage is dependent on the gametophyte for nutrition.
- It does not carry out photosynthesis and relies on the gametophyte for sustenance.

4. **Understanding Pteridophytes:**
- Pteridophytes are vascular plants that include ferns and horsetails.
- In the life cycle of pteridophytes, the main plant body is the sporophyte.

5. **Defining Sporophyte:**
- The sporophyte is a multicellular diploid organism.
- "Diploid" means it has two sets of chromosomes (2n).
- The sporophyte represents the complete plant body in pteridophytes.

6. **Final Answer:**
- Therefore, in bryophytes, the dominant phase in the life cycle is the **gametophyte** plant body, and in pteridophytes, the main plant body is the **sporophyte**.

**Final Answer:**
In bryophytes, the dominant phase in the life cycle is the **gametophyte** plant body, but in pteridophytes, the main plant body is the **sporophyte**.

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