integument

Question 1

4 layers of epidermis

Answer 1

stratum basale
stratum spinosum - desmosomes
stratum granulosum - kerathyalin granules/ lamellar bodies
stratum corneum - cornified squamous cells / keratin/non-polar lipids

stratum lucideum would be between granulosum and corneum where epidermis is thicker in some areas

Question 2

what other cells found in epidermis

Answer 2

melanocytes - allow pigmentation / release melanin
(mostly in basal layer)

langerhans cells - immune system

Question 3

function of dermis

Answer 3

tensile strength (collagen)
elasticity (elastin)
blood/nerve supply for epidermis

(repair - fibroblasts fill gap with new collagen)

Question 4

epidermis function

Answer 4

barrier - infection/waterproof(dehydration)/injury/ solar radiation

site for vitamin D production (UV)

Question 5

where do u find hard/soft keratin

Answer 5

hard - nails/hair

soft -skin

Question 6

what are desmosomes

Answer 6

connections between cells - hold cytoskeletons together = making skin a good barrier
found in stratum spinousum
gives a spiny appearance

Question 7

what do these receptors detect + where are they found

Answer 7

merkel cells - light touch

pacinian corpuscle - pressure (HYPODERMIS)

meissner’s corpuscle - light touch (DERMAL PAPILLA-dermis)

Question 8

why doesn’t a paper cut hurt

Answer 8

epidermis does not have blood vessles/nerves

Question 9

what is wrapped around each hair follicle

Answer 9

erector pilli muscle - control angle of hair

mechanosensitive nerve

Question 10

role of melanocytes from protection from UV

Answer 10

uv–> damage to keratinocytes–> DNA Damage –> MSH signal to melanocytes–> melanin–via dendrites–> keratinocytes to protect from further damage

Question 11

lichenification

Answer 11

extreme from of hyperkeratosis = rubbing of skin –> thickening of stratum corneum

Question 12

3 types of UV

Answer 12

UVA - longest
UVB
UVC - blocked by ozone layer

Question 13

which type of skin cancer is most dangerous

Answer 13

melanoma = melanocytes (due to rapid seed)

non-melanoma = keritanocytes

• squamous cell carcinoma
• basal cell carcinoma

Question 14

partial thickness / full thickness burns

Answer 14

partial = epidermis (+ a bit of dermis)

full = epidermis + dermis
-loss of pinprick sensation

Question 15

psoriasis

Answer 15

extensor surfaces - focal/well demarcated plaques with silvery white scale

reduced epidermal transit time from 30days–> 6days
causing hyper proliferation and thickening of epidermis

Question 16

bacteria that causes impetigo

Answer 16

staph.aureus / strep . pyrogenes

causes blisters/extrudate with golden crusts on skin

Question 17

which skin conditions require immediate attention (2ww)

Answer 17

squamous cell carcinoma

melanoma