skin P1

Question 1

what are the functions of the skin?

Answer 1

• protect
• excrete salts, water, and organic waste by integumentary glands
• maintain main body temp
• produce melanin
• produce keratin
• synthesize vitamin D
• store lipids
• detect touch. pressure, pain, and temp stimuli

Question 2

what are the 3 primary layers of the skin called

Answer 2

1. epidermis
   2, dermis
   3, hypodermis

Question 3

describe the epidermis layer (functions etc…)

Answer 3

• is the outer layer of skin
• is a stratified barrier
• mostly made of keratinocytes
• has no blood circulation

Question 4

describe the dermis layer (functions etc…)

Answer 4

• helps the skin stay together
• is alive/has blood circulation
• has 7 layers
• protein fibres for strength
• is vascular

Question 5

describe the hypodermis layer (functions etc…)

Answer 5

• is the lowest layer
• subcutaneous ( not the skin )
• adipose tissue (fats are)
• these fats are mobilised in starvation

Question 6

with epithelial tissue, what does ‘simple’ and ‘stratified’ mean

Answer 6

simple = single/ 1 layer
stratified = stacked/ multiple layers

Question 7

what does squamous, cuboidal and columnar look like

Answer 7

squamous = squashed
cuboidal = cube
columnar = columns

Question 8

how many layers are in the epidermis

Answer 8

4 layers

Question 9

what are the name of the layers in the epidermis (top to bottom)

Answer 9

stratum corneum
stratum granulosum
stratum spinosum
stratum basale

Question 10

describe the stratum corneum (horny layer)

Answer 10

has dead, dried-out hard cells that dont have a nuclei.
flakes off the body
are formed in horns

Question 11

describe the stratum granulosum layer

Answer 11

it dehydrates the cells that are being pushed towards the surface
cross-links the keratin fibres
waxy material is secreted into intercellular spacing to fill the gaps

Question 12

describe the stratum spinosum layer

Answer 12

has intercellular bridges called desmosomes

cells become increasingly flattened as they move up

Question 13

describe the stratum basale layer

Answer 13

are tall (columnar) regenerative cells
as the cell divides, the daughter cell migrates upwards to replenish the layer above
never runs out

Question 14

what are hemidesmosomes?

Answer 14

they help anchors the stratum basale to the dermis

Question 15

what are desmosomes

Answer 15

they anchor neighbouring cells in the epidermis

Question 16

true or false, the stratum corneum be completely removed

Answer 16

true

Question 17

how many layers are in thick skin

Answer 17

5 layers

Question 18

what is the extra layer in thick skin called

Answer 18

stratum lucidum

Question 19

what are the 2 layers under the dermis called

Answer 19

• papillary layer

- reticular layer

Question 20

describe the papillary layer

Answer 20

it consists of highly vascularised tissue with is used for nourishment

Question 21

describe the reticular layer

Answer 21

its a ‘mesh-like’ structure of collagen and elastin fibres

- for strength

Question 22

what do both the papillary and reticular layer contain

Answer 22

• blood vessels
• lymphatics
• sensory nerve fibres
• accessory structure

Question 23

what does plexus mean

Answer 23

a network of something

e.g network of blood vessels or nerves

Question 24

what is the cutaneous plexus

Answer 24

a network of blood vessels that are present at the junction of the dermis/hypodermis

Question 25

what does the cutaneous plexus do

Answer 25

supplies the hypodermis, deep dermis, the capillaries for the hair follicles and sweat glands

Question 26

what is the subpapillary plexus

Answer 26

- it branches off the cutaneous plexus and lies deep to the papillary layer of the dermis - is a network of blood vessels

Question 27

what does the subpapillary plexus do

Answer 27

supplies oxygen and nutrients to the upper dermis and epidermis

Question 28

describe what the hypodermis is

Answer 28

- is the subcutaneous layer - dominated by adipocytes that produce subcutaneous fat - the subcutaneous fat stores energy and provides insulation - common layer for vaccinations to go

Question 29

describe what a 1st degree burn is

Answer 29

- is superficial, only involves outer layer of epidermis - has red/pink, dry look - is painful - usually no blisters - remains a water and bacterial barrier - heals 3-10 days

Question 30

describe a normal 2nd degree burn

Answer 30

- involves epidermis + varying amounts of dermis - is painful - looks moist, red and blistered - heals in approx 1-2 weeks with good dressings

Question 31

describe a deeper 2nd degree burn

Answer 31

- involves epidermis + dermis - may include a whiteish, waxy looking areas - hair follicles and sweat glands may stay intact - may have some loss of sensation and scarring - heal time = 1 month

Question 32

describe a 3rd degree burn

Answer 32

- is a full thickness burn ( goes through all layers till the subcutaneous tissue) - may involve muscle and bone - can vary in colour = waxy white to deep red or black - has a hard, dry. leathery look - no pain in the areas as sensory nerve endings = destroyed - may require skin graft - weeks to regenerate and scarring