What is the function of plasmodesmata in plants?

• A. They connect plant cells and allow transport and communication.
• B. They are chloroplasts involved in photosynthesis.
• C. They are rigid cell wall components preventing plasmolysis.
• D. They store starch in vacuoles.

Answer: (A)

Plasmodesmata are channels that connect the cytoplasm of adjacent plant cells, enabling transport and communication between them. Through these microscopic passages, small molecules, ions, sugars, and signaling RNAs can move from cell to cell, creating a continuous cytoplasmic network (the symplast) that coordinates activity across tissues. The channels are lined by the plasma membrane and contain a desmotubule from the endoplasmic reticulum, and their openness can be adjusted by callose deposition to regulate what passes through. This function is quite different from chloroplasts (which perform photosynthesis), from rigid cell wall components that prevent plasmolysis, or from starch storage in vacuoles (starch is stored in plastids). So the primary role is to connect plant cells and permit transport and communication.