outer tissue of leaves. stems. roots. flowers. and seeds.

Merriam-Webster Online Dictionary
epidermis (noun)
a) the outer epithelial layer of the external integument of the animal body that is derived from the embryonic epiblast , specifically the outer nonsensitive and nonvascular layer of the skin of a vertebrate that overlies the dermis
b) any of various animal integuments
a thin surface layer of tissue in higher plants formed by growth of a primary meristem
epidermis (Wikipedia)
Microscopic image of the epidermis, which constitutes the outer layer of skin, shown here by the white bar
Epidermal layers.png
Microscopic image showing the layers of the epidermis. The stratum corneum appears more compact in this image than above because of different sample preparation.
Part ofSkin
SystemIntegumentary system
Anatomical terms of microanatomy

The epidermis is the outermost of the three layers that make up 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 released from the body into the atmosphere through transepidermal water loss. The epidermis is composed of multiple layers of flattened cells that overlie a base layer (stratum basale) composed of columnar cells arranged perpendicularly.

The rows of cells develop from stem cells in the basal layer. Cellular mechanisms for regulating water and sodium levels (ENaCs) are found in all layers of the epidermis.

The word epidermis is derived through Latin from Ancient Greek epidermis, itself from Ancient Greek epi, meaning 'over, upon' and from Ancient Greek derma, meaning 'skin'. Something related to or part of the epidermis is termed epidermal.

The human epidermis is a familiar example of epithelium, particularly a stratified squamous epithelium

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