Ch. 5 Integumentary System Flashcards
(104 cards)
what does skin consist of?
1) epidermis (stratified squamous epithelium)
2) dermis (connective tissue)
3) hypodermis or sub cutaneous tissue (connective tissue)
what cells are part of the epidermis? (4) (KMLM)
1) keratinocytes (produces keratin)
2) melanocytes (produces melanin)
3) langerhans cells
4) merkel cells
what is the most common cell in the epidermis?
keratinocytes
where are melaninocytes located?
in the deep epidermis
what the langerhans cells part of?
the immune system
where are merkel cells located and what are they
deep in the epidermis and they are touch receptors
what do keratinocytes do?
form deep in the epidermis and shed at the surface
as cells pass through the epidermis what happens?
they change (keratinization)
how many epidermal layers are in thin skin?
4
how many epidermal layers are in thick skin?
5
what is considered thick skin?
palms, fingertips and soles
what is an example of keratinization?
large scales of epidermal tissue are sloughed off (psoriasis)
strata of the epidermis from deepest to most superficial
1) stratum basale
2) stratum spinosum
3) stratum granulosum
4) stratum Lucidum
5) stratum corneum
what is the only stratum of the epidermis to have thick skin?
stratum lucidum
how thick is stratum basale?
a single layer thick
what does stratum basale have?
stem cells that divide and replace shed cells
how many layers does stratum spinosum consist of?
8-10 layers
what does stratum spinosum produce?
keratin fibers
how many layers does stratum granulosum consist of?
2-5
what type of cells does stratum granulosum consist of?
dying, flat cells with keratohyalin granules (lamellar bodies)
what do keratohyaline granules (lamellar bodies) contain?
lipid and keratin fibers
what does stratum lucidum consist of?
several cells that appear glassy and consist of flattened, dead cells filled with keratin
what does stratum corneum contain?
25 or more layers of flat, overlapping, dead cells full of keratin
what happens to the layers of the stratum corneum?
they are gradually shed at the top