Dermatology

Question 1

whats the difference between superficial and deep fascia

Answer 1

superficial = subcutaneous
its fatty and loose

deep fascia = tough and sheet like
dense connective tissue, white and glistening appearance

Question 2

name the 2 superficial veins of the upper limb and what aspect of the limb they travel on

Answer 2

cephalic vein - along the lateral aspect of limb

basilic vein - along medial aspect of limb

Question 3

name the 2 superficial veins of the lower limb and what aspect of limb they travel on

Answer 3

great saphenous vein - along midline of leg

small saphenous vein - along posterior midline of lower leg

Question 4

what is vena comitantes

Answer 4

when veins benefit from pulsation of the artery when enclosed in a vascular sheath

Question 5

where is the most common area for venous ulceration to occur

Answer 5

the gaiter area - medial aspect of distal leg

Question 6

what is the general pathophysiology of venous ulceration

Answer 6

venous blood pressure increases
damages blood vessels, which become leaky
proteolytic enzymes and free radicals released, which leak into surrounding tissue and damage it
skin breaks down but cannot heal due to the poor blood supply

Question 7

where do all axillary lymphatics drain into

Answer 7

subclavian lymphatics

Question 8

where do all lower limb lymphatics eventually drain into

Answer 8

the external iliac nodes –> common iliac nodes –> lumbar lymphatics

Question 9

what cells is the epidermis made up of

Answer 9

ectoderm cells that form a single layer periderm

Question 10

do the periderm cells remain attached forever

Answer 10

no - they cast off

Question 11

what are the 4 layers that make up the epidermis

Answer 11

keratin layer - corneocytes, waterproof barrier 💦
granular layer - 2 or 3 layers of flat cells
prickle cell layer - has lots of desmosomes
basal layer - 1 cell thick, v metabolically active

Question 12

what cell type is the majority of the epidermis made up of

Answer 12

95% keratinocytes - they are stratified squamous epithelium

Question 13

what is the keratin Layer formed from

Answer 13

the terminal differentiation of keratinocytes to corneocytes

Question 14

in which layer of the epidermis is the cell nucleus lost

Answer 14

the granular layer

Question 15

at what stage in foetal development are the 4 layers of the epidermis created

Answer 15

16 weeks

Question 16

when in foetal development are hair follicles and other appendages developed

Answer 16

26 weeks

Question 17

what non-keratinocyte epidermal cells also reside in the epidermis

Answer 17

melanocyte
langerhans cells
Merkel cells

Question 18

what structure do melanocyte cells contain that converts tyrosine to melanin

Answer 18

melanosomes

Question 19

where do melanocytes migrate from in the first 3 weeks of development

Answer 19

from neural crest to epidermis

Question 20

name the cell described as a pigment producing dendritic cell

Answer 20

melanocytes

Question 21

where does the precursor for langerhan cells originate

Answer 21

the bone marrow

Question 22

what layer in the epidermis to langerhan cells reside and what are they involved in

Answer 22

prickle cell layer

involved in the skin immune system

Question 23

name the antigen presenting cell of the epidermis

Answer 23

the langerhan cell

Question 24

which cells are known as mechanoreceptors and may become malignant

Answer 24

Merkel cells - they’re needed for the ‘light touch sensation’

they can become malignant Merkel cell carcinoma - caused by viral infection

Question 25

what structures make up the pile-sebaceous unit

Answer 25

hair
hair follicle (the bit of hair under skin)
Arrector pilli muscle
sebaceous gland

Question 26

name the 3 phases of growth in hair follicles

Answer 26

anagen - growing
catagen - involuting
telogen - resting (shedding phase)

Question 27

what are the 3 layers of the demo-epidermal junction

Answer 27

lamina lucida
lamina densa
sub-lamina densa

Question 28

what cells are found in the dermis

Answer 28

fibroblasts, macrophages, mast cells, lymphocytes and langerhan cells

Question 29

which somatic sensory receptors detect pressure

Answer 29

pacinian receptors

Question 30

which somatic sensory free nerve endings detect vibration

Answer 30

meissners endings

Question 31

which skin gland produces the natural moisturiser sebum

Answer 31

sebaceous gland

Question 32

which skin gland produces the oily fluid that goes on to become BO

Answer 32

apocrine gland - part of the pill-sebacous unit

Question 33

which skin glands main purpose is thermoregulation and covers most of the body surface

Answer 33

eccrine glands