Lecture 10

Question 1

Blister

Answer 1

Seperation of dermis from epidermis

Acute severe friction

Question 2

Callus

Answer 2

Thickening of epidermis

Chronic friction

Question 3

Epidermis

Answer 3

Superficial epithelial tissue

Question 4

Dermis

Answer 4

Deeper fibrous connective tissue

Vascularized

Question 5

Hypodermis

Answer 5

Fatty layer under dermis
Superficial fascia, subcutaneous layer
Adipose and areolar connective tissue
Thickens during weight gain

Question 6

Epidermis

Answer 6

Different layers of cells at different life stages

5 strata

Question 7

Stratum basal

Answer 7

Cuboid cells right above dermis
Cells are constantly dividing
Contains melanocytes

Question 8

Stratum spinosum

Answer 8

Cells look like that have sharp spiny edges
Attached to one another with desmosomes
Pre-keratin

Question 9

Stratum granulosum

Answer 9

Cells have keratohyalin granules

Thick cell membrane

Question 10

Stratum lucidum

Answer 10

Only in areas with thick skin
Cells are dead, with no organelles or nucleus
Filled with keratin

Question 11

Stratum corneum

Answer 11

Top most layer
Cells are dead
No organelles/nucleus
Filled with keratin

Question 12

Keratinocytes

Answer 12

Cells of the skin

Produce keratin

Question 13

Melanocytes

Answer 13

Produce melanin

Increase production in response to UV light

Question 14

Merkel’s cells

Answer 14

Touch receptors of the skill

Connected to nerves

Question 15

Dendritic cells

Answer 15

Immune cells in skin

Question 16

Dermal papillae

Answer 16

Epidermal/dermal ridges
Increase friction and grip
Sweat pores open along the crests of the ridges

Question 17

Three pigments

Answer 17

1. Melanin
2. Carotene
3. Hemoglobin

Question 18

Melanin

Answer 18

Yellow to reddish to brown to black
Different types
Without it, epidermis would be translucent
Provides protection from UV rays

Question 19

Carotene

Answer 19

Yellow-orange pigment

Accumulates in stratum corneum and hypodermis

Question 20

Melanin granules

Answer 20

On superficial side of keratinocytes

Question 21

Light skin

Answer 21

Melanin is digested by lysosomes short distance from basal layer
Not digested in dark skin

Question 22

Dangers of UV rays

Answer 22

Sunlight decreases production of folic acid (anticancer)

Production of melanin to prevent loss of folic acid

Question 23

Essentialness of UV rays

Answer 23

Needed during pregnancy to prevent neural tube defects

Sunlight stimulates deep epidermis production of VitD

Question 24

Freckles

Answer 24

Increased melanin in stratum basale

Due to repeated exposure to light

Question 25

Moles

Answer 25

Clusters of melanocytes converted into a melanin containing cell

Question 26

Transdermal patch

Answer 26

Drug molecules diffuse through epidermis into dermis | Works well with small, lipid soluble molecules

Question 27

Appendages of skin

Answer 27

Nails, hair/follicles, sebaceous glands, sweat glands

Question 28

Nails

Answer 28

``` Modified epidermis, dead keratinized cells Hard keratin (unlike skin) ```

Question 29

Nail bed

Answer 29

Deep layers of epidermis

Question 30

Pink part of nail

Answer 30

Due to rich underlying capillaries

Question 31

Lunule

Answer 31

Thick bed called nail matrix | Active growing part

Question 32

Hair

Answer 32

Flexible strand of dead cells filled with keratin Root and shaft Melanocytes at base of hair follicle - different proportions in types of melanin give colours Stem cells found in external root sheath

Question 33

Round hair shaft

Answer 33

Straight hair

Question 34

Oval hair shaft

Answer 34

Wavy hair

Question 35

Flat hair shaft

Answer 35

Kinky hair

Question 36

Grey hair

Answer 36

Decreased melanin and colourless air bubbles

Question 37

Hair follicle

Answer 37

Hair bulb and hair follicle receptor Stem cells found in external root sheath Hair papilla with capillaries

Question 38

Arrector pili

Answer 38

Raiser of hair, goose bumbs | Small muscle from follicle to epidermis

Question 39

Sebaceous glands

Answer 39

Oil glands of skin Associated with hair follicles Secretion soften and lubricates hair and skin Holocrine secretion: miniature explosion, death of cell

Question 40

Acne

Answer 40

So much sebum: blocks the gland White head is oxidized to black head Infected sebaceous glands give pimples

Question 41

Burns

Answer 41

Tissue damage due to heat, electricity, radiation, extreme friction, chemicals Infection or dehydration

Question 42

First degree burn

Answer 42

Damage to epidermis | Redness, swelling, pain

Question 43

Second degree burn

Answer 43

Damage to epidermis and upper dermi | Blisters

Question 44

Third degree burn

Answer 44

Entire thickness of skin White, red or black discolouration Autograft required

Question 45

Autograft

Answer 45

Skin from other parts of patients body grafter to burned area

Question 46

Artificial skin

Answer 46

Skin made from bovine collagen dermis and epidermis made of silicon