Plasmodesmata are

Options

A. membrane connecting the nucleus with plasmalemma
B. connections between adjacent cells
C. lignified cemented adjacent cells
D. locomotary structures

Answer

**Step-by-Step Solution:**

1. **Understanding Plasmodesmata**: Plasmodesmata are specialized structures found in plant cells that facilitate communication and transport between adjacent cells.

2. **Cell Structure Context**: In plant cells, there is a rigid cell wall surrounding each cell. This cell wall is a dead structure that provides support and protection.

3. **Middle Lamella**: Between the cell walls of two adjacent plant cells, there is a layer called the middle lamella. This layer is primarily composed of pectins and acts as a cementing substance that helps hold the cells together.

4. **Cytoplasmic Connections**: To allow for communication between the plant cells, the cytoplasm of adjacent cells can extend through the cell walls, forming connections. These connections are crucial for the exchange of nutrients, signaling molecules, and other substances.

5. **Definition of Plasmodesmata**: The strands of cytoplasm that extend through the cell walls and connect adjacent plant cells are known as plasmodesmata. Each strand acts as a bridge of cytoplasm, allowing for direct communication between the cells.

6. **Conclusion**: Therefore, plasmodesmata can be defined as connections between adjacent plant cells, facilitating intercellular communication.

**Final Answer**: Plasmodesmata are connections between adjacent cells.

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