the skin Flashcards
What are the three layers of the skin?
epidermis, dermis, hypodermis/subcutaneous layer
describe the structure of the epidermis
outermost layer of the skin
5 layers:
- horny layer - flat cells, sheds continuously
- clear layer - 3-4 cells thick, palms & soles, protects from friction
- granular layer - 2-4 cells thick, cells begin to die & flatten
- prickle cell layer - 10-20 cells thick, keratin & melanin production
- basal cell layer - single layer, column-shaped cells, produces new cells
describe the structure of the dermis
middle layer
thickness varies
2 layers:
1. papillary layer
- wavy appearance
- blood & lymph vessels
- nerve endings
- joins dermis & epidermis
2. reticular layer
- dense, fibrous
- collagen, elastin & reticulin tissues
- protect & repair
describe the structure of the subcutaneous layer
fat cells
protection
sweat glands
sebacious glands
nerve endings
arrector pili muscles
hair follicles
hair shaft
papule
small solid raised lump
open pores
stretched ducts or hair follicles
pustule
small raised area containing bacterial infection
impetigo
contagious bacterial infection
sores and blisters
broken capillaries
pink-red lines on the skin
boils
infected hair follicles
herpes
viral infection
contagious
herpes simplex - cold sores. eyes, genitalia
herpes zoster - shingles (rash)
tinea corporis
ringworm
fungal infection
rash in a circle
milia
small, raised, pearly-white bumps
folliculitis
infected hair follicles
carbuncles
clusters of boils
scabies
parasite
itchy, rash, spots
silvery lines
pediculosis
lice
head lice/pubic lice
eczema
dry, itchy skin
psoriasis
scaly, flaky skin. overproduction of skin cells
dermatitis
eczema caused by contact with harsh substances
acne vulgaris
blocked hair follicles and sebaceous glands
acne rosacea
redness, sensitivity to water and skincare products
dryness and swelling around the eyes
cysts
fluid-filled lump just beneath the skin
overproduction of keratin
moles
small coloured spots on the skin
harmless, but if they change it can be a sign of cancer
skin tags
small growths that hang off the skin
keloid scars
overproduction of collagen after injury
urticaria
hives/welts/nettle rash
sebhorrea
red, itchy rash and white scales
dandruff when on the head
hyper-pigmentation
darker patches of skin
overproduction of melanin
hypo-pigmentation
lighter patches of skin
decreased melanin production
vitiligo
xanthomas
skin lesions containing cholesterol and fats
raised, yellow-coloured, waxy in appearance