Question

What is the meaning of Plasmodesmata?

Answer 1

Plasmodesmata (singular: plasmodesma) are tiny channels that connect the cytoplasm of neighbouring plant cells directly, forming living bridges between them. Thousands of plasmodesmata, or connections between daughter cells may arise. Plasmodesmata plays a crucial role for the cell.

Complete answer:
Plasmodesmata are intercellular pores or channels that connect adjacent plant cells, permitting membrane and cytoplasmic continuity. They are important intercellular trafficking, communication, and signalling channels in plant development and defence.
Plasmodesmata (singular: plasmodesma) are tiny channels that connect the cytoplasm of nearby plant cells, forming living bridges. Hundreds of thousands of plasmodesmata may develop, connecting the daughter cells. When parts of the endoplasmic reticulum are stuck across the middle lamella while new cell walls are generated between two newly separated plant cells, primary plasmodesmata occur. These eventually create cell-to-cell cytoplasmic connections. Pits are generally found next to each other in adjacent cells.
Plasmodesmata play a role in intercellular communication, allowing chemicals to travel directly from one cell to the next. It's been claimed that plasmodesmata, like gap junctions in animal cells, mediate transfer between adjacent plant cells. These are microscopic channels of plants facilitating transport and communication between individual cells. Unlike animal cells, plant cells are protected by an impermeable cell wall; and as such, plasmodesmata are required for intercellular activity.
Cells can utilize both passive and active transport to move molecules and ions through the passage. A plasmodesma is constructed of three main layers, the plasma membrane, the cytoplasmic sleeve, and the desmotubule. Plant cells being linked together by thin strands.

Note:-
Plasmodesmata have been found to transport proteins (including transcription factors), short interfering RNA, messenger RNA (mRNA), viroids, and viral genomes from one cell to another. The tobacco mosaic virus MP-30 is an example of a viral movement protein. MP-30 is hypothesised to bind to the virus's own genome and transport it through plasmodesmata from infected to uninfected cells.