Skin

Question 1

Layers of skin

Answer 1

Stratum basale - lowest
Stratum spinosum
Stratum graulosum
Stratum lucidum
Stratum corneum - most superficial

Question 2

Functions of skin

Answer 2

Protection- waterproof layer protects deeper more delicate structures. Non specific defence against physical agents/ chemicals and dehydration
Regulation of body temp- core temp 36.8
Formation of vitamin D - lipid based substance is converted to vitamin d in sunlight
Cutaneous sensation - sn=ensory receptors in dermis sensitive to touch,pressure,temp or pain
Absorption- nicotine patch
Excretion - NaCl in sweat

Question 3

Regulation of body temp

Answer 3

Body temp increases heat loss increases by dilation of arterioles in dermis increasing blood flow to the skin
Stimulates sweat glands and more sweating until body temp falls to core temp

Question 4

Aging skin

Answer 4

Ski and mucuousmembrane becomes thin and fragile
Fewer capillaries and cells proliferation is decreased resulting in slower wound healing
Less sensory receptors so bruise easier
Skin dry and wrinklier

Question 5

Skin in developing foetus

Answer 5

By end of 4 weeks a thin outer layer of flattened cells cove the embryo
Further development until 24 weeks
Hair begins to grow at 9- 12th week
Fingernails >10weeks
Toenails - 18 weeks

Question 6

Wound healing stages

Answer 6

Inflammation
Proliferation
Maturation

Question 7

Inflammation

Answer 7

Within the first few hours, the wound surfaces becomes inflamed a blood clot fora s and cell debris fills gap between them

Question 8

Profileration

Answer 8

Epidermis meets and grows upwards until thickness is restored
Clot above new tissue is the scab
Granulation tissue phagocyte and fibroblast develop and invade the cot and restore blood suppply to the wound
Fibroblasts continue to secrete collagen fibres occurs and strength of wound increases

Question 9

Maturation

Answer 9

Granulation tissue replaced by fibrous scar tissue
Scar tissue less vascular
During fibrosis scar tissue replaces granulation tissue until full thickness is reached

Question 10

Pressure sores what are they

Answer 10

Larg amount of pressure applied to an area of skin over time
Extra pressure disrupts blood flow through skin
Without blood supply affected skin becomes oxygen starved and begins to break down and ulcers form.

Question 11

Where are pressure sores form

Answer 11

Bum
Elbow
Sacrum
Trochanter - hips
Spine/shoulders
Heels
Occipital area
Toes