Stratum germinativum
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Stratum germinativum | |
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Section of epidermis. | |
A diagrammatic sectional view of the skin (magnified). | |
Gray's | subject #234 1063 |
Stratum germinativum (also stratum basale or basal cell layer) is the layer of keratinocytes that lies at the base of the epidermis immediately above the dermis. It consists of a single layer of tall, simple columnar epithelial cells lying on a basement membrane. These cells undergo rapid cell division, mitosis to replenish the regular loss of skin by shedding from the surface. About 25% of the cells are melanocytes, which produce melanin which provides pigmentation for skin and hair.
[edit] Pathology
All melanocytes have the capacity to migrate widely in the embryo, and therefore a cancer of a melanocyte, a melanoma, will spread (metastasize) very easily. For this reason, melanomas are often fatal, and when surgically removed, a lot of surrounding tissue must be taken as well.
Albinism is a recessive hereditary condition in which the melanocytes do not procuce melanin. People appear very pale and have blue eyes.
Basal cell carcinoma is a relatively benign form of skin cancer which arises from this layer of cells.
[edit] Additional images
[edit] External links
- Histology at BU 08422loa - "Integument: thick skin"
- MedEd at Loyola medicine/dermatology/skinlsn/stgerm.htm
Skin • Sweat glands • Sebaceous glands • Hair (Hair follicle) • Nails
Skin
Epidermis (Stratum corneum, Stratum lucidum, Stratum granulosum, Stratum spinosum, Stratum germinativum/basale)