Question

The fine cytoplasmic strands that interconnect the protoplasts of parenchyma cells are called ..........

Answer 1

The cytoplasm of neighbouring plant cells is connected to each other by the help of channels. They form bridges to transport the materials from one cell to the other cell. It also helps in the communication and signalling between the plant cells.

Complete Answer:
The fine cytoplasmic strands that interconnect the protoplasts of parenchyma cells are called plasmodesmata​.
Plasmodesmata are cell to cell communication channels that connect the neighbouring plant cells to each other, establishing living bridges between them. The plasmodesmata, which penetrate both the primary and secondary cell walls, allow certain molecules to pass directly from one cell to another cell.
Plasmodesmata are common and abundant in the walls of columns of cells that lead toward sites of intense secretion, such as in nectar-secreting glands.
The structure of plasmodesmata are roughly cylindrical, membrane-lined channels with a diameter of 20 to 40 nm.
The functions of Plasmodesmata are intercellular communication, that is they allow molecules to pass directly from cell to cell.it is a transport between adjacent plant cells. Plasmodesmata also make junctions from cell to cell, allowing numerous cells to work together towards a common goal.
It is also used by cells in the phloem, and symplastic transport is used to regulate the sieve-tube cells by the companion cells.
Parenchyma cells are relatively large, thin walled cells arranged loosely; there are intracellular spaces among them. The protoplast of these cells contains chloroplast, amyloplast and crystals.

Note:
Plasmodesmata are used by cells in the xylem phloem, and used in symplastic transport to regulate the sieve-tube cells by the companion cells. It is formed when the newly cell wall is synthesized between two newly divided plant cells. A typical plant cell has plasmodesmata connecting it with adjacent cells equating to between 1 and 10 per ${µm^2}$. It is absent in animal cells.