What are the channels through cell walls that connect the cytoplasms of adjacent cells called?

The channels that allow for communication and transport of materials between the cytoplasms of adjacent plant cells are known as plasmodesmata. These structures are specialized for the transmission of substances such as ions, small molecules, and even larger macromolecules like proteins and RNA between cells, facilitating intercellular communication and coordination of developmental processes in plants.

Plasmodesmata consist of a narrow tube of endoplasmic reticulum that traverses the cell wall, forming a continuous link between the cytoplasm of neighboring cells. This unique feature enhances the ability of plant cells to function cooperatively within tissues, responding to signals and sharing vital resources efficiently.

In contrast, cell junctions generally refer to various structures in animal cells that connect cells and include tight junctions, adherens junctions, and desmosomes, each serving different functionalities. The extracellular matrix serves as a scaffold for cells, providing structural support and facilitating cell communication, but it does not directly connect cytoplasms. Gap junctions, while similar in function to plasmodesmata, are specific to animal cells and allow molecules to pass directly between the cytoplasms of adjacent cells, but they are structurally different and do not occur in plant cells.