For Mucor zygospore is

Options

A. Haploid
B. Thick-wall resting spore
C. Asexual spore
D. Spore that germinates to form zoospores .

Answer

### Step-by-Step Solution:

1. **Identify the Organism**: The question pertains to Mucor, which is a member of the group known as phycomycetes, commonly referred to as lower fungi or algal fungi.

2. **Understand Zygospore Formation**: The zygospore is a type of sexual spore produced during sexual reproduction in Mucor. This occurs when two specialized structures called zygophores come into contact.

3. **Zygophore Characteristics**: Zygophores are the mycelium structures that contain gametangia. There are two types of zygophores: one is of the positive strain (plus) and the other is of the negative strain (minus).

4. **Formation of Gametangia**: When the plus and minus zygophores meet, they form swollen regions known as gametangia. These gametangia are separated from the rest of the hyphae by a structure called the suspensor.

5. **Fusion of Protoplasts**: The protoplasts (the living part of the cell) of the gametangia from both the plus and minus strains fuse together. This fusion results in the formation of a zygote.

6. **Development of Zygospore**: Following the formation of the zygote, it develops into a zygospore. The zygospore is characterized as a thick-walled resting spore, which is typically dark brown or black and rounded in shape.

7. **Nature of the Zygospore**: Since the zygospore is formed post-fertilization and is a result of the fusion of two gametangia, it is not haploid. It is a sexual spore, which distinguishes it from asexual spores.

8. **Conclusion**: Based on the characteristics and formation process, the zygospore in Mucor is a thick-walled resting sexual spore.

### Final Answer:
The zygospore for Mucor is a thick-walled resting sexual spore.

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