Parenchymas

Part of speech: noun

Definitions

1. The functional tissues in plants or animals that perform their specific physiological roles, primarily consisting of living cells with thin walls and the ability to divide; in plants, these cells are involved in photosynthesis, storage, and tissue repair; in animals, these tissues constitute the essential parts of an organ responsible for its main function
2. Living cells composing the essential parts of an organ or plant tissue responsible for carrying out vital activities, characterized by capacity for growth and regeneration; in botanical contexts, these include cells that facilitate photosynthesis and nutrient storage; in zoological contexts, these are the portions performing the critical functions of organs
3. The primary tissue in plants or animals consisting of living cells that contribute to the main activity of the organ, including support for metabolism and storage; in plants, these tissues enable processes such as photosynthesis and healing; in animals, these make up the functional portion of organs distinct from structural elements

Etymology: "Parenchymas" is the plural of "parenchyma", a term in biology for the soft tissue cells that make up much of an organ or plant. The singular traces back to Ancient Greek "parénkhuma", meaning "anything poured in beside", built from "pára", "beside", and "énkhuma", "instillation" or the contents of a vessel. The Greek anatomist Erasistratus applied it to the peculiar substance of the lungs, liver, kidneys and spleen, which he imagined was formed separately by the veins running into those organs, as though poured in alongside them. The ancient anatomical sense was based on a mistaken idea of how these organs were made. The modern meaning, of living cells that carry out vital functions and can grow and regenerate, grew out of that old label, which was retained even after the underlying theory was abandoned.

Synonyms: tissues, cells