What does parenchyma mean?
Parenchyma is a type of tissue composed of relatively unspecialized, living cells. In plants, it forms much of the softer internal structure of leaves, stems, roots, fruits, and seeds. Depending on its location and function, it may carry out photosynthesis, store starch or water, provide mechanical support, or help repair damaged tissue. Some specialized kinds have distinct names: chlorenchyma contains abundant chloroplasts and performs photosynthesis, while storage parenchyma holds reserves of food or water. In anatomy, parenchyma also means the functional tissue of an organ rather than its connective framework. This medical use is especially common for the immune-system organs, including the lymph nodes, spleen, and thymus, whose lymphoid parenchyma contains the cells responsible for immune responses. The word is therefore useful in both botany and medicine for describing basic tissue organized around the active functions of living organisms.
Plant tissue composed of relatively unspecialized living cells, commonly associated with photosynthesis, storage, support, or tissue repair.
"Water stored in the stem's parenchyma helps the plant survive dry conditions."
In botany, specialized forms include photosynthetic chlorenchyma and starch-storing storage parenchyma.
The functional, soft tissue of an anatomical organ, especially lymphoid tissue containing immune cells.
"Doctors examined the lymphoid parenchyma of the enlarged lymph nodes."
This sense belongs primarily to anatomy and medicine and is especially associated with lymphoid organs.
The plural is used when referring to distinct masses or regions of parenchyma.
"The radiologist identified small parenchymas within both lungs."
Plants rely on parenchyma for much more than photosynthesis: it also stores food, helps wounds heal, and can be transformed into new organs.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does parenchyma come from?
The word comes through Latin from Greek parenkhyma, a coined noun formed from parenkhein, meaning “to pour in beside” or “pour in close to.” It originally referred to the cellular tissue of plants, in contrast to more rigid supporting tissues. Its anatomical use developed later by analogy with the soft, functionally active substance of organs. The adjective parenchymatous preserves the same Greek and Latin roots.
Related word forms
How parenchyma is actually used
In plant biology, the term is a standard anatomical and physiological category. In medicine, it is used chiefly for lymphoid or solid-organ tissue; the anatomical sense is more technical than the botanical one.