Search results
Results From The WOW.Com Content Network
The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. [1] The epidermal layer provides a barrier to infection from environmental pathogens [2] and regulates the amount of water released from the body into the atmosphere through transepidermal water loss.
The epidermis contains no blood vessels, and cells in the deepest layers are nourished almost exclusively by diffused oxygen from the surrounding air [6] and to a far lesser degree by blood capillaries extending to the outer layers of the dermis. The main type of cells that make up the epidermis are Merkel cells, keratinocytes, with melanocytes ...
Micrograph of keratinocytes, basal cells and melanocytes in the epidermis Keratinocytes (stained green) in the skin of a mouse. Keratinocytes are the primary type of cell found in the epidermis, the outermost layer of the skin. In humans, they constitute 90% of epidermal skin cells. [1]
The stratum corneum (Latin for 'horned layer') is the outermost layer of the epidermis. Consisting of dead tissue, it protects underlying tissue from infection, dehydration, chemicals and mechanical stress. It is composed of 15–20 layers of flattened cells with no nuclei and cell organelles.
The clear epidermal cells exist in a single layer and do not contain chloroplasts, because the onion fruiting body (bulb) is used for storing energy, not photosynthesis. [3] Each plant cell has a cell wall, cell membrane, cytoplasm, nucleus, and a large vacuole. The nucleus is present at the periphery of the cytoplasm.
The epidermis is the outermost cell layer of the primary plant body. In some older works the cells of the leaf epidermis have been regarded as specialized parenchyma cells, [1] but the established modern preference has long been to classify the epidermis as dermal tissue, [2] whereas parenchyma is classified as ground tissue. [3]
Merkel cell. Merkel cells are found in the skin and some parts of the mucosa of all vertebrates. In mammalian skin, they are clear cells found in the stratum basale [2] [3] (at the bottom of sweat duct ridges) of the epidermis approximately 10 μm in diameter. They are oval-shaped mechanoreceptors essential for light touch sensation and found ...
Histologic image showing a section of epidermis. Stratum basale labeled near bottom. The stratum basale (basal layer, sometimes referred to as stratum germinativum) is the deepest layer of the five layers of the epidermis, the external covering of skin in mammals. The stratum basale is a single layer of columnar or cuboidal basal cells.