Pavement cells are a cell type found in the outmost

epidermal The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water relea ...

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 a sturdy layer. This irregular shape that each individual cell takes on can be influenced by the

cytoskeleton The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is com ...

and specific proteins. As the leaf grows, the pavement cells will also grow, divide, and synthesize new

vacuoles A vacuole () is a membrane-bound organelle which is present in plant and fungal cells and some protist, animal, and bacterial cells. Vacuoles are essentially enclosed compartments which are filled with water containing inorganic and organic mo ...

, plasma membrane parts, and cell wall components. A thick external cell wall influences the direction of growth by impeding expansion towards the outside of the cell and instead promote expansion parallel to the epidermis layer. Data suggest that waviness of pavement cells may be initiated by compressive mechanical stresses in a feedback loop that solidifies and augments cell shapes resulting in local reinforcement of the cell wall.

References

Plant cells {{Cell-biology-stub