Absence of sex organs and asexual spores in the life cycle is associated with

Options

A. Ascomycetes
B. Phycomycetes
C. Deuteromycetes
D. basidiomycetes

Answer

To solve the question regarding the absence of sex organs and asexual spores in the life cycle, we can follow these steps:

### Step 1: Understand the Groups of Fungi
Fungi are classified into different groups based on their reproductive structures and methods. The main groups include:
- Phycomycetes
- Ascomycetes
- Basidiomycetes
- Deuteromycetes

### Step 2: Analyze Each Group
1. **Phycomycetes**: Known as lower fungi, they reproduce asexually through spores like zoospores and aplanospores, and sexually through zygospores.
2. **Ascomycetes**: They produce asexual spores called conidia and sexual spores known as ascospores, which are formed in fruiting bodies called ascocarps.
3. **Basidiomycetes**: This group is characterized by the absence of asexual spores and sex organs. They reproduce sexually through the fusion of two different hyphae (plus and minus types), resulting in the formation of basidiospores on a structure called basidiocarp.
4. **Deuteromycetes**: Also known as imperfect fungi, they reproduce asexually through conidia, but they do not have a sexual reproduction phase.

### Step 3: Identify the Correct Group
From the analysis, we see that:
- The **Basidiomycetes** are the only group that lacks both sex organs and asexual spores. They reproduce sexually but do not have asexual reproduction.

### Conclusion
Thus, the absence of sex organs and asexual spores in the life cycle is associated with **Basidiomycetes**, also known as club fungi.

### Final Answer
The correct answer is **Basidiomycetes** (option 4).

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