In ferns, circinate ptyxis (vernation) is defined as

Options

A. arrangement of leaf gaps in stems
B. coiling of young leaves
C. arrangement of sori on leaves
D. attachement of ramenta on young parts.

Answer

**Step-by-Step Solution:**

1. **Understanding Circinate Ptyxis (Vernation):**
- Circinate ptyxis refers to the coiled arrangement of young leaves (fronds) in ferns. This coiling is a protective mechanism during the development of the leaves.

2. **Definition of Ptyxis:**
- Ptyxis is the term used to describe the way a leaf is folded or arranged during its developmental stage.

3. **Characteristics of Circinate Ptyxis:**
- In ferns, young leaves emerge in a coiled form, which is referred to as circinate. This coiling protects the delicate leaf tissues as they grow and unfold.

4. **Importance of Circinate Ptyxis:**
- The circinate arrangement allows for the safe development of the leaves, preventing damage from environmental factors until they are fully mature and can expand.

5. **Conclusion:**
- Therefore, circinate ptyxis (or vernation) in ferns is defined as the coiled arrangement of young leaves that protects them during their growth.

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