diacytic stomata possess subsibiary cells.

Options

A. parallel to guard cells.
B. in rings around guard cells
C. At right angles to guards cells
D. unequal

Answer

To answer the question about diacytic stomata and their subsidiary cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Stomata**: Stomata are small openings found on the epidermis of plant leaves and stems that allow for gas exchange. They are crucial for photosynthesis and respiration.

2. **Identify Types of Stomata**: There are several types of stomata, including:
- Anomocytic (irregular)
- Paracytic (parallel)
- Diacytic (cross-celled)
- Anisocytic (unequal)
- Actinocytic (radiated)

3. **Focus on Diacytic Stomata**: The question specifically asks about diacytic stomata. Diacytic stomata are also known as cariophilaceous or cross-celled stomata.

4. **Characteristics of Diacytic Stomata**: In diacytic stomata, the subsidiary cells are positioned at right angles to the guard cells. This means that they share a common wall with the guard cells, forming a cross-like arrangement.

5. **Evaluate the Options**: The options provided are:
- A) Parallel to guard cells
- B) In rings around guard cells
- C) At right angles to guard cells
- D) Unequal

Based on the characteristics of diacytic stomata, the correct answer is **C) At right angles to guard cells**.

### Final Answer:
Diacytic stomata possess subsidiary cells that are at right angles to the guard cells.

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