Epidermis

Question 1

Keratinocytes

Answer 1

-Most abundant cell type in epidermis
-Produce fibrous, water-resistant protein called keratin which is linked together by desmosomes into layers

Question 2

Melanocytes

Answer 2

-Produce melanin pigment granules responsible for skins color
-Melanin production increases with exposure to UV radiation in sunlight

Question 3

Langerhans’ cells

Answer 3

macrophages (type of white blood cell) involved in immunity

Question 4

Merkel cells

Answer 4

touch receptors located in deepest layer of epidermis

Question 5

Layers of Epidermis

Answer 5

Four or five separate layers
1) stratum basale
2) stratum spinosum
3) stratum granulosum
4) stratum lucidum
5) stratum corneum

Question 6

Stratum Basale

Answer 6

-deepest layer of epidermis
-contains most of dividing cells

Question 7

Stratum Spinosum

Answer 7

-produces intermediate filaments of pre-keratin protein

Question 8

Stratum Granulosum

Answer 8

-cells that are thinning and filling with protein granules
-cells die as they are pushed to the outside

Question 9

Stratum Lucidum

Answer 9

-thin, translucent layer of dead cells between the stratum granulosum and stratum corneum
-only present in thick skin

Question 10

Stratum Corneum

Answer 10

-has 20 to 30 layers of dead but fully keratinized cells
-contently replaced by deeper layers