In corona radiata, the cells are held together by

Options

A. Cytoplasmic connections
B. Cell membrane interdigitations
C. Thin layer of intercellular cement
D. Hyaluronic acid.

Answer

**Step-by-Step Solution:**

1. **Understanding Corona Radiata**: The corona radiata is a layer of cells that surrounds the ovum (egg) in the female reproductive system. It consists of multiple layers of granulosa cells.

2. **Identifying the Components**: The question asks what holds these cells together. We have four options to consider:
- a. Cytoplasmic connections
- b. Cell membrane interdigitation
- c. Thin layer of intercellular cement
- d. Hyaluronic acid

3. **Analyzing Each Option**:
- **Cytoplasmic connections**: These refer to direct connections between the cytoplasm of adjacent cells, but they are not the primary means of adhesion in the corona radiata.
- **Cell membrane interdigitation**: This describes the interlocking of cell membranes, but again, it is not the main factor in the adhesion of the cells in the corona radiata.
- **Thin layer of intercellular cement**: This could refer to substances that help hold cells together, but it is not the specific substance that is known to be present in the corona radiata.
- **Hyaluronic acid**: This is a glycosaminoglycan that is known to be present in the extracellular matrix and is specifically involved in the adhesion of the granulosa cells in the corona radiata.

4. **Conclusion**: Based on the analysis, the cells in the corona radiata are primarily held together by hyaluronic acid. Therefore, the correct answer is **option D: hyaluronic acid**.

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