Peritheciurn refers to

Options

A. Flask shaped ascocarp with apical opening.
B. Cup shaped ascocarp
C. Fruiting body of 1basidiomycetes
D. Eye spot of euglenoids

Answer

### Step-by-Step Solution:

1. **Understanding the Term "Perithecium":**
- The term "perithecium" refers to a specific type of fruiting body found in certain fungi. It is essential to recognize that this structure is associated with the reproduction of fungi.

2. **Identifying the Characteristics of Perithecium:**
- A perithecium is typically described as a flask-shaped ascocarp. This means it has a rounded body that resembles a flask, which is crucial for its identification.

3. **Recognizing the Opening of Perithecium:**
- One of the defining features of a perithecium is that it has an apical opening. This opening is where the spores are discharged, allowing for the reproduction and dispersal of the fungal spores.

4. **Evaluating the Options Given:**
- The question provides multiple options regarding what "perithecium" refers to. We need to evaluate these options based on our understanding of its characteristics:
- Option 1: Flask shape, ascocarp with apical opening (Correct)
- Option 2: Cup-shaped ascocarp (Incorrect)
- Option 3: Fruiting body of the Basidiomycetes (Incorrect)
- Option 4: Support of the Euclenoid (Incorrect)

5. **Conclusion:**
- Based on the evaluation, the correct answer is that "perithecium" refers to a flask-shaped ascocarp with an apical opening.

### Final Answer:
Perithecium refers to a flask-shaped ascocarp with an apical opening.

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