Stratum spinosum
From Wikipedia, the free encyclopedia
Stratum spinosum | |
---|---|
Section of epidermis. | |
Gray's | subject #234 1063 |
In the skin, the stratum spinosum is a multi-layered arrangement of cuboidal cells that sits beneath the stratum granulosum. Adjacent cells are joined by desmosomes giving them the spiny appearance from which their name is derived. Their nuclei are often darkened (a condition called pyknosis), which is an early sign of cell death. Their fate is sealed because the nutrients and oxygen in interstitial fluid have become exhausted before the fluid is able to reach them by diffusion.
Cells of the stratum spinosum actively synthesize intermediate filaments called cytokeratins which are composed of keratin. These intermediate filaments are anchored to the desmosomes joining adjacent cells to provide structural support, helping the skin resist abrasion.
[edit] Additional images
[edit] External links
- Histology at BU 08422loa - "Integument: thick skin"
Integumentary system - edit |
---|
Skin | Sweat glands | Sebaceous glands | Hair | Nails |
Skin |
Epidermis (Stratum corneum, Stratum lucidum, Stratum granulosum, Stratum spinosum, Stratum germinativum/basale) |
Dermis | Subcutis |