companionCellterm
Companion cell is a term used in biology to describe a cell that is associated with another cell, often in a symbiotic relationship. The term is commonly used in the context of plant biology, where it refers to a cell that is physically connected to another cell and provides it with nutrients or other substances. Companion cells are typically found in the phloem tissue of plants, which is responsible for transporting sugars and other organic compounds throughout the plant. The companion cell is often larger than the sieve-tube member cell it is associated with and is connected to it by plasmodesmata, which are channels that allow for the exchange of materials between the two cells. The companion cell plays a crucial role in the functioning of the sieve-tube member cell, which is responsible for the transport of sugars and other organic compounds. In some cases, companion cells may also be found in animal biology, where they are involved in the regulation of cell growth and differentiation. The term "companion cell" is also used in the context of stem cell research, where it refers to a cell that is used to support the growth and differentiation of other cells.