Dermo-epidermal junction, and structure + function of dermal components

Question 1

describe the key roles of the dermo-epidermal junction

Answer 1

support, anchorage, adhesions, growth and differentiation of basal cells
semi-permeable membrane acting as barrier and filter

Question 2

what different cell types are found in the dermis

Answer 2

mainly fibroblasts, macrophages, mast cells, lymphocytes, Langerhans cells

Question 3

what different components make up the dermis

Answer 3

ground substance, cells, fibres, muscles, blood vessels, lymphatics, nerves

Question 4

what types of fibres are found in the dermis

Answer 4

collagen and elastin

Question 5

what are the 3 different layers that make up the epidermal junction, from superficial to deep

Answer 5

lamina lucida, lamina densa, sub-lamina densa zone

Question 6

describe the supply and structure of blood vessels in the dermis

Answer 6

supply is greater than metabolic need, vessel walls well supported, horizontal plexuses

Question 7

describe the structure of the lymphatic vessels in the dermis

Answer 7

sub-epidermal mesh networks, smaller non-contractile vessels, larger contractile lymphatic trunks

Question 8

describe the drainage of the lymphatic vessels in the dermis

Answer 8

continual drainage of plasma proteins, extravasated cells and excess interstitial fluid

Question 9

describe the immune functions of the lymphatics in the dermis

Answer 9

immune surveillance by circulating lymphocytes and Langerhans cells, channelling of micro-organisms and toxins

Question 10

describe the somatic sensory(dermatomes) nerve supply in the dermis

Answer 10

free nerve endings, special receptors

Question 11

what special sensory nerve receptors are found in the dermis

Answer 11

Pacinian(pressure) and Meissners(vibration) corpuscles

Question 12

what is involved in the autonomic nerve supply in the dermis

Answer 12

blood vessels, nerves and glands

Question 13

what different glands are found in the skin

Answer 13

sebaceous, eccrine, apocrine

Question 14

what type of secretion does sebaceous glands produce, and opening into what

Answer 14

holocrine secretion, opening into pituitary canal

Question 15

describe the distribution of sebaceous glands

Answer 15

widely distributed, largest glands at face and chest

Question 16

what is produced by sebaceous glands

Answer 16

produce sebum(consists; squalene, wax esters, TG and FFA)

Question 17

what are the functions of sebaceous glands

Answer 17

control moisture loss and protection from fungal infection

Question 18

what other structure do apocrine sweat glands develop as part of

Answer 18

the pilosebaceous unit

Question 19

where are apocrine sweat glands found

Answer 19

axillae and perineum

Question 20

describe what is produced by apocrine sweat glands

Answer 20

oily fluid, odorous after bacterial decomposition

Question 21

describe where eccrine sweat glands are found

Answer 21

whole skin surface, palms, soles and axillae in particular

Question 22

describe the nerve supply of eccrine sweat glands

Answer 22

sympathetic cholinergic nerve supply

mental, thermal and gustatory stimulation

Question 23

what are the functions of the eccrine sweat glands

Answer 23

cooling by evaporation, moisten palms/soles to aid grip