Answer:
a. Stratum corneum 5. : Thick superficial layer of flat, keratinized, dead cells; responsible for dandruff.
b. Stratum granulosum 3.: Cells flatten and fill with keratin, resulting in a grainy appearance.
c. Stratum lucidum 4. : Clear layer found only in thick skin; cells full of keratin.
d. Stratum basale 1. : Deepest layer; site of rapid cell division and melanin production.
e. Stratum spinosum 2.: Live keratinocytes connected by desmosomes produce pre-keratin
Explanation:
The epidermis has five layers, starting from the deepest one they are:
The stratum basale: is the layer that has the germinative cells, called keratinocytes.
The stratum spinosum: the keratinocytes are connected, and they produce the precursor of keratin and lipids.
The stratum granulosum: the name of this stratum is due to the appearance of the cells. They produce keratohyalin, and the lipids produced in the previous layer are released, creating the layer that protects the skin against dehydration.
The stratum lucidum: They are only in thick skin, like the one that is in the sole of our feet. The cells do not have a nucleus. They are filled with keratin, which is the component of thick skin.
The stratum corneum: the more superficial layer, it is made of dead cells filled with keratine. When new cells ascend to this stratum, the old ones have to be removed by exfoliation or natural peeling.
