what is epidermis in plants

The epidermis is the outermost layer of cells covering the stem, root, leaf, flower, fruit, and seed parts of a plant. It is a fundamental plant tissue that provides a protective barrier against mechanical injury, water loss, and infection. The epidermis and its waxy cuticle also regulate transpiration, increase water absorption, and secrete substances. The epidermis plays a crucial role in regulating gas exchange in plant cells. Various modified epidermal cells, such as stinging hair, hypodermis, trichome, root hair, and cystolith, have specific functions. The epidermis is formed from the protoderm and is the first tissue to differentiate during plant development.