The animals do not graze on ferns because most of ferns contain a phenolic derivative called

Options

A. Phlobaphene
B. Fuschin solution
C. TNT
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks why animals do not graze on ferns. It indicates that there is a specific compound present in ferns that deters animals from feeding on them.

2. **Identifying the Plant Group**: Recognize that ferns belong to a group of plants known as pteridophytes. These are vascular plants that reproduce via spores and do not produce seeds.

3. **Recognizing the Compound**: The transcript mentions that ferns contain a phenolic derivative. Phenolic compounds are known to have various effects on the taste and palatability of plants.

4. **Naming the Compound**: The specific phenolic derivative that is mentioned in the transcript is called "phlobaphene." This compound contributes to the bitter taste of ferns.

5. **Conclusion**: Because phlobaphene has a strong bitter taste, it discourages animals from grazing on ferns, leading to the conclusion that animals do not feed on them due to this compound.

**Final Answer**: The phenolic derivative present in ferns that prevents animals from grazing on them is called phlobaphene.

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