Peristome teeth of moss shows

Options

A. Hydrochasy
B. Xerochasy
C. Hydrotropism
D. Chemotropism.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the function of peristome teeth in mosses and which phenomenon they are associated with: hydrochase, xerochase, hydrotropism, or chemotropism.

2. **Identifying Peristome Teeth:**
Peristome teeth are structures found in mosses. They are projections that play a key role in the dispersal of spores.

3. **Function of Peristome Teeth:**
These teeth have a valve-like structure that regulates the release of spores from the moss capsule.

4. **Conditions for Spore Release:**
The release of spores occurs under specific conditions, particularly at low humidity or dry conditions. This is when the peristome teeth allow the spores to spill out from the capsules.

5. **Mechanism of Spore Dispersal:**
Once released, the spores float away and disperse into the environment, which is crucial for the reproduction of mosses.

6. **Identifying the Correct Phenomenon:**
The process by which spores are released from the capsule in dry conditions is termed "Xerotracheae." This term specifically refers to the dispersal mechanism that occurs in dry environments.

7. **Conclusion:**
Therefore, the correct answer to the question is **Xerotracheae** (option number 2).

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