What are the successive structures formed in course of sexual reproduction in Rhizopus ?

Options

A. Zygospore, progametagium , gametangium, zygophore
B. Progametangium, zygophore, gametangium, zygospore
C. Progametangium, gametangium, zygospore, zygophore
D. Zygophore, progametangium, gametangium,zygospore

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The organism in question is Rhizopus, which is a genus of fungi that can be saprophytic (feeding on dead organic matter) or parasitic.

2. **Understand the Habitat**: Rhizopus is typically found in moist or damp environments, which is important for its growth and reproduction.

3. **Describe the Vegetative Structure**: The vegetative structure of Rhizopus consists of multinucleated and branched hyphae. These hyphae play a crucial role in the organism's life cycle.

4. **Initiation of Sexual Reproduction**: The first structure formed during sexual reproduction is the zygophore. Zygophores are specialized branches that develop from the somatic hyphae of Rhizopus.

5. **Formation of Pro-gametangium**: The zygophores bear structures called pro-gametangia. These are the initial structures that will lead to the formation of gametangia.

6. **Development of Gametangia**: The pro-gametangium has a terminal portion known as the gametangium. This is where the gametes will be produced.

7. **Fusion of Gametangia**: The protoplasts (the living part of the cell) of two opposite strain gametangia fuse together. This fusion results in the formation of a diploid mass.

8. **Formation of Zygospore**: The diploid mass that forms from the fusion of gametangia develops into a zygospore, which is the final structure in the sexual reproduction process of Rhizopus.

9. **Summary of Successive Structures**: The successive structures formed during sexual reproduction in Rhizopus are:
- Zygophore
- Pro-gametangium
- Gametangium
- Zygospore

**Final Answer**: The successive structures formed in the course of sexual reproduction in Rhizopus are zygophore, pro-gametangium, gametangium, and zygospore.

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