<Tr> <Th> FMA </Th> <Td> 70596 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terms of microanatomy (edit on Wikidata) </Td> </Tr> <P> 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 . </P> <P> 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 . </P>

What is the upper most layer of skin