Basis of differentiation | Epidermis | Dermis |
Definition | Epidermis is the outer layer of cells, which cover the body of an organism | Dermis is a thick layer of living cells below the epidermis, containing blood vessels, sweat glands, hair follicles, and nerve endings |
Depth and thickness | Is the superficial, thin cell layer | Is the thickest layer of skin, and deeper than the epidermis |
Presence of cells | Contain both living and dead cells | All cells are living cells |
Presence of blood vessels | Epidermis does not contain blood vessels | Dermis has an extensive network of blood vessels |
Origin | Originates from the ectoderm | Originates from the mesoderm |
Components | Consists of keratin in humans and suberin in plants | Consists of hair follicles, nails, sweat glands, and apocrine glands |
Structure | Is made up of stratified layers of flattened epithelial cells | Is made up of dense irregular connective tissue |
Presence of ECM | Contains tightly packed cells without an ECM | Contains an ECM |
Presence of nerves | No nerve receptors are present in the epidermis | Has sensory nerve endings present |
Mechanism of obtaining nutrients | Obtains essential nutrients and oxygen by diffusion from the dermis | Obtains oxygen and nutrients from the blood capillaries |
Cell types | Contains melanocytes, langerhans cells, merkel's cells, and keratinocytes | Contains fibroblasts, macrophages, and adipocytes |