Plant cell the major classes of cells and tissues of roots, stems, leaves, flowers, and reproductive structures, each of which may be composed of several cell types. Parenchyma cells are living cells that have functions ranging from storage and support to photosynthesis (mesophyll cells) and phloem loading (transfer cells). Apart from the xylem and phloem in their vascular bundles, leaves are composed mainly of parenchyma cells. Some parenchyma cells, as in the epidermis, are specialized for light penetration and focusing or regulation of gas exchange, but others are among the least specialized cells in plant tissue, and may remain totipotent, capable of
Pavement cells Pavement cells Pavement cells are a cell type found in the outmost epidermal layer of plants. The main purpose of these cells is to form a protective layer for the more specialized cells below. This layer helps decrease water loss, maintain an internal temperature, keep the inner cells in place, and resist the intrusion of any outside material. They also separate stomata apart from each other as stomata have at least one pavement cell between each other. They do not have a regular shape. Rather, their irregular shapes help them to interlock with each other like puzzle pieces to form