Skin Anatomy 1

Question 1

Outline melanin production function of skin

Answer 1

Produces melanin, which protects underlying tissue from ultraviolet radiation

Question 2

Outline keratin production role of skin

Answer 2

Produces keratin, which protects against abrasion and serves as a water repellent

Question 3

Outline skin lipid storage role

Answer 3

Stores lipids in adipocytes in the dermis and in adipose tissues in the subcutaneous layer

Question 4

Outline detection function of skin

Answer 4

Detect touch, pressure, pain, and temperature stimuli, and relay that information to the nervous system

Question 5

What tissue types is skin made up of

Answer 5

All 4 tissue types.
Epithelial, connective, muscle, and nervous tissues

Question 6

What are the 3 primary layers of skin

Answer 6

Epidermis - outer skin
Dermis - skin
Hypodermis - bellow skin

Question 7

3 features of epidermis

Answer 7

Stratified barrier
Mostly keratinocytes (protein cells)
No blood circulation - a vascular

Question 8

2 features of Dermis

Answer 8

Protein fibres for strength (collagen and elastin)
Vascular (nourishes epidermis)

Question 9

Feature of Hypodermis

Answer 9

Adipose tissue

Question 10

What tissue dominates in the epidermis

Answer 10

Epithelial tissue

Question 11

Simple vs Stratified tissues

Answer 11

Simple - single layer of tissue cells
Stratified = stacked layers of tissue cells

Question 12

3 types of epithelia

Answer 12

Squamous - squashed/scales
Cuboidal
Columnar

Question 13

4 layers of epidermis, from superficial to deep

Answer 13

Stratum corneum
Stratum granulosum
Stratum spinosum
Stratum basale

Question 14

Stratum corneum cell types

Answer 14

Dead, dried out hard cells without nuclei

Question 15

Stratum granulosum cell types

Answer 15

Contains granules that promote cell dehydration. cross linking of keratin fibre (dead cells cannot attach to eachother). Waxy material secreted into the intercellular spaces

Question 16

Stratum spinosum cell type

Answer 16

Intercellular bridges (desmosomes) link cells together within epidermis
Cells become increasingly flattened as the move upward

Question 17

Stratum basale cell type

Answer 17

Columnar regenerative stem cells. As basal cell decides, a daughter cell migrates upwards to replenish the layer above

Question 18

Desmosomes vs Hemidesmosomes

Answer 18

Desmosomes - anchor adjacent/neighbouring cells within the epidermis
Hemidesmosomes - anchor stratum basale to the dermis

Question 19

Outline thin skin

Answer 19

4 layers
“Come get some burgers”
Top layer is dead (stratum corneum)

Question 20

Outline thick skin

Answer 20

5 layers
“Come lets get some hand burgers”
Found of palms of hands and feet
No hair
Extra epidermal layer - stratum lucidum
Outer 2 layers are dead (stratum corneum and stratum lucidum)

Question 21

Outline the dermis

Answer 21

Situated below the epidermis and anchors via Hemidesmosomes
Is not shed
Divided into two layers - papillary layer and reticular layer
Both layers contain blood vessels, lymphatics, sensory nerve fibres, and accessory structures

Question 22

Papillary layer vs reticular layer

Answer 22

Papillary layer - consists of highly vascularised tissues (for nourishment)
Reticular layer - mesh like structure of collagen and elastin fibres (for strength)

Question 23

Two plexuses of the dermis

Answer 23

Cutaneous plexus
Subpapilliary plexus

Question 24

Cutaneous plexus

Answer 24

Network of blood vessels present at the junction of dermis/hypodermis.
Supplies the hypodermis, deeper dermis, including the capillaries for hair follicles and sweat glands

Question 25

Subpapillary plexus

Answer 25

Branches from the cutaneous plexus Lies deep to the papillary layer of the dermis Network of blood vessels providing O2 and nutrients to the upper dermis and epidermis

Question 26

Define plexus

Answer 26

Plexus refers to a network of blood vessels or nerves

Question 27

Outline the hypodermis

Answer 27

The “subcutaneous” layer Classical anatomy does not consider as a part of skin (hubs192 does) Dominated by adipocytes that produce subcutaneous fat The subcutaneous fat stores energy and provides insulation Common site of injections using hypodermic needles

Question 28

What fat is consumed during fasting

Answer 28

Subcutaneous fat stores are consumed during fasting

Question 29

Outline first degree burns

Answer 29

Superficial only - only involve outer layers of the epidermis Red/pink, dry, painful Usually no blisters Skin remains a water and pathogenic barrier Usually heals within 3-10 days

Question 30

Outline a normal second degree burn

Answer 30

Epidermis + varying amounts of dermis Painful, moist, red, and blistered Usually heals in approx 1-2 weeks (needs good dressing)

Question 31

Outline a deeper second degree burn

Answer 31

May include whiteish, waxy looking areas Hair follicles, sweat glands may remain intact Usually heal in one month May have some loss of sensation and scaring

Question 32

Outline a third degree burn

Answer 32

full thickness burn - extends into subcutaneous tissue, may involve muscle/bone. Varied colour from waxy white through to deep red or black Hard, dry and leathery skin No pain in these areas as sensory nerve endings are destroyed May require skin draft Weeks to regenerate + scaring