PHYSIOLOGY - skin structure

Question 1

which embryological layer does the epidermis come from

Answer 1

ectoderm

Question 2

which embryological layer does the dermis come from

Answer 2

mesoderm

Question 3

where does the neural crest come from embryologically

Answer 3

melanoblasts

Question 4

what is the gastrulation stage of embryology

Answer 4

organisation into germ layers

Question 5

how long does full regeneration of the skin (epidermis) take

Answer 5

28 days

Question 6

what are blaschkos lines

Answer 6

the lines in which skin develops in

Question 7

what is the outer most layer of the epidermis

Answer 7

keratin layer

Question 8

what layer of the epidermis is internal to the keratin layer

Answer 8

granular layer

Question 9

what layer of the epidermis is internal to the granular layer

Answer 9

prickle cell layer

Question 10

what layer is internal to the prickle cell layer

Answer 10

basal layer

Question 11

which layer is internal to the basal layer

Answer 11

dermis

Question 12

what is the keratin layer also known as

Answer 12

stratum corneum

Question 13

what 4 cells are in the keratin layer

Answer 13

keratinocytes
corneocytes
fillagrin protein
keratin protein

Question 14

what are corneocytes

Answer 14

dead keratinocytes

Question 15

where do keratinocytes originate

Answer 15

basal layer

Question 16

what is the function of keratinocytes

Answer 16

vitamin D synthesis

Question 17

when are keratinocytes activated

Answer 17

sunlight

Question 18

what 3 cells are in the granular layer

Answer 18

lipids
odland bodies
birbeck granules

Question 19

what does the prickle cell layer consist of

Answer 19

desmosomes (connections)

Question 20

what 2 types of cells are in the prickle cell layer

Answer 20

birbeck granules

Langerhans cells

Question 21

what do birbeck granules look like on histology

Answer 21

tennis rackets

Question 22

what type of cells are Langerhans cells

Answer 22

dendritic cells

Question 23

what does the prickle cell layer look like on histology (in comparison to the other layers)

Answer 23

‘prickly’ goes up and down in waves bc of the polyhedral cells

Question 24

where is the basal layer

Answer 24

at the bottom

Basal = ‘Bottom’

Question 25

what 2 cells are found in the basal layer

Answer 25

melanocytes | merkel cells

Question 26

what do melanocytes do

Answer 26

convert tyrosine to melanin pigment

Question 27

what are merkel cells

Answer 27

receptors - have nerves attached to them

Question 28

which 2 layers is the dermal-epidermal junction between

Answer 28

basal layer of epidermis and the dermis

Question 29

which layer contains muscles, blood vessels, lymphatics and nerves

Answer 29

the dermis

Question 30

what is one of the main cells in the dermis what is its function

Answer 30

fibroblasts produces collagen

Question 31

what type of corpuscle is in the dermis

Answer 31

meissener corpuscle

Question 32

what type of corpuscle is in the subcutaneous fat

Answer 32

pacinian corpuscle

Question 33

what are the 3 hair follicle growth phases

Answer 33

Anagen Catagen Telogen (get in the ACT)

Question 34

which hair follicle growth phase is the growing phase

Answer 34

anagen

Question 35

in which hair follicle phase does the hair involute (curve)

Answer 35

catagen

Question 36

what happens in the telogen phase of hair follicle growth

Answer 36

resting, nothing hair can fall out

Question 37

what type of cells are nail cells

Answer 37

specialised keratin cells

Question 38

what is the growth rate of nails

Answer 38

0.1mm per day

Question 39

what do sebaceous glands produce

Answer 39

sebum

Question 40

where do you find sebaceous glands

Answer 40

mainly face and chest (but everywhere) | around hair follicles

Question 41

which group of people to sebaceous glands not work in

Answer 41

pre pubertal

Question 42

purpose of sebaceous glands

Answer 42

protect from fungal infection | control moisture loss

Question 43

what do apocrine glands produce

Answer 43

sweat

Question 44

where do you find apocrine glands (2)

Answer 44

axilla | perineum

Question 45

which skin glands produce a smell

Answer 45

apocrine glands

Question 46

where are eccrine glands (3)

Answer 46

everywhere esp; soles of feet palms of hands

Question 47

how do eccrine glands release their produce

Answer 47

exits skin directly | Eccrine glands = Exit skin directly = are Everywhere

Question 48

how do apocrine glands release their produce

Answer 48

via hair follicles

Question 49

what is hyperkeratosis

Answer 49

increased thickness of keratin layer

Question 50

what is parakeratosis

Answer 50

persistence of nuclei in the keratin layer

Question 51

should there normally be nuclei in the keratin layer if there is, what has happened example

Answer 51

no cell turnover has been too quick psoriasis

Question 52

how does psoriasis present on histology

Answer 52

parakeratosis - nuclei in keratin layer

Question 53

what is acanthosis

Answer 53

increased thickness of epithelium

Question 54

what is another word for acanthosis

Answer 54

hyperplasia

Question 55

what is papillomatosis

Answer 55

irregular epithelial thickening | think papilloma = benign tumour = irregular in shape

Question 56

what is spongiosis

Answer 56

oedema/fluid between cells

Question 57

which cells does the skin have that are important for immune defence (2)

Answer 57

Langerhans cells | T cells

Question 58

general function of keratin layer

Answer 58

waterproof barrier

Question 59

what is the function of blood vessels in the skin

Answer 59

temperature regulation by vasoconstriction/vasodilatation

Question 60

the production of melanin form melanocytes is significant because...

Answer 60

protects DNA from UV