Marrasknahk e. epidermis koosneb mitmekihilisest lameepiteelist, millel on suurema või väiksema tugevusega sarvnahakiht. Epidermises puuduvad veresooned, närvikiud tungivad sinna pärisnahast ja moodustavad epidermise sügavamates kihtides vabu närvilõpmeid. Marrasknaha funktsioon: kaitse kuivamise, alajahtumise, vee aurumise eest.
The epidermis is the uppermost or epithelial layer of the skin. It acts as a physical barrier, preventing loss of water from the body, and preventing entry of substances and organisms into the body. Its thickness varies according to the body site. The epidermis consists of stratified squamous epithelium. That means it consists of layers of flattened cells.