The gemmule formation is the form of asexual reproduction in class of porifera

Options

A. calcarea
B. demospongia
C. hexactinellida
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Gemmules:**
- Gemmules are specialized structures formed by certain organisms, particularly in the phylum Porifera (sponges). They serve as a means of asexual reproduction and are capable of surviving harsh environmental conditions such as drying out, freezing, or low oxygen levels (anoxia).

2. **Identifying the Classes of Porifera:**
- The phylum Porifera is divided into four main classes:
- Calcarea
- Demospongiae
- Hexactinellida
- (The fourth class is not mentioned in the transcript but is known as Homoscleromorpha.)

3. **Gemmule Formation in Porifera:**
- Gemmules are primarily produced by members of the classes Calcarea, Demospongiae, and Hexactinellida. They are formed as a response to adverse environmental conditions and can remain dormant until conditions improve.

4. **Analyzing the Options:**
- The question provides four options regarding which class of Porifera gemmule formation occurs:
- A) Calcarea
- B) Demospongiae
- C) Hexactinellida
- D) All of these
- Since gemmules are found in all three classes mentioned (Calcarea, Demospongiae, and Hexactinellida), the correct answer is option D.

5. **Conclusion:**
- The gemmule formation is a form of asexual reproduction that occurs in all the classes of Porifera listed in the options. Therefore, the answer to the question is D) All of these.

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