ch 3

Question 1

layer of skin, top to bottom

Answer 1

epidermis
dermis
hypodermis

Question 2

epidermis

Answer 2

Avascular, no direct blood vessel supply

Keratinizedsquamous epithelium
- keratinocytes, melanocytes, merkel cells, langerhans cells

Question 3

Keratinocytes

Answer 3

(tough, carry melanin granules)

□ The main ingredient in these cells iskeratinprotein, manufactures and stores the protein
□ Stratified
□ When we are exposed to sun we contain more melanin taken up by the keratinocytes

Freckles are caused by keratinocytes taking in more melanin

Question 4

melanocytes

Answer 4

(colour granules, UV protection)

□ Produce melanin, 8% of the cells are melanocyts, dont contain the melanin.

□ Bottom layer of the epidermis

□ Moles are exagerated growths of melanocytes, highly regenerated cells

Question 5

merkel cells

Answer 5

(sensory)

Attached to the epidermis, bottom layer

Question 6

langerhans cell

Answer 6

(macrophages)

□ Part of immune system

Question 7

5 layers of epidermis

Answer 7

(stratum spinosum)

basale
spinosum
granulosum
lucidum
corneum

Question 8

basale

Answer 8

(deep)

Furthest away from external environment

Question 9

spinosum

Answer 9

(spider)

□ Alive layer, contains Langehans cells
□ Dehydrated but still attached
□ Little replication

Question 10

granulosum

Answer 10

(water proofing, last area of oxygenation…too far)

□ Oxygen would be used up and the cells start to die, release a substance makes it a hydrophobic barrier
Glycolipidis released

Question 11

lucidum

Answer 11

(thick skin, dead)

□ Just above the granlosum

Question 12

corneum

Answer 12

(dead but horny (cornified) cells) You will sluff off lots during your lifetime!

□ Dead cells, thick layer of just dead cells.

Question 13

dermis

Answer 13

○ Wavelike appearance, to increase surface area for blood vessels
	§ Leather is made from dermis layer
○ Connective tissue cells
○ Nerve fibers
○ Blood vessels

Question 14

2 layers of dermis

Answer 14

§ Papillary 20%
§ Reticular 80%

Tattoos go into the reticular region.

Question 15

hypodermis

Answer 15

Not a part of the integumentary system, comprised of fat.

Hypo = low or below…below the Dermis
- Sometimes calledsubcutaneouslayer

Insulates the body, allows movement, jellylike, between the skin and the muscle

Question 16

hypodermis

○ Formed by areolar and adipose tissue

Answer 16

§ Adiposepredominates

§ Allows movement of muscle tissue below

§ The site of subcutaneous FAT (different b/w sexes)

§ Females store fat in hip region, males in abdominal region

Question 17

skin colour

Answer 17

Pigments from melanin, carotene and hemoglobin

Question 18

melanin

Answer 18

○ Precursor:tyrosine
§ Ranges from yellow-red-brown-black
§ Freckles/moles are localized melanin
§ Vitiligo
§ Albinism
□ Lose the ability to produce melanin
○ Eumalaninandpheomelanin
§ Eumelanin is yellow to red

Pheomelanin is darker

Question 19

carotene

Answer 19

○ Yellow-orange from veggies

accumulates in stratum corneum and fat of hypodermis

Question 20

hemoglobin

Answer 20

○ O2 carrying part of RBC

Where ever there are capillaries there’s hemoglobin!

Gives skin pinkish hue when you blush…if you blush!

Question 21

birthmark

Answer 21

• areas of skin with too many capillaries

Question 22

skin appendages

Answer 22

Hair
○ dead keratinized cells secreted from the living hair follicle

Sebaceous glands(grease)
○ secrete sebum which protects and conditions the skin

Sweat glands
○ secrete sweat (a blood filtrate) which is mostly water (99%)

Nails
○ scale-like modification of the epidermis - the human equivalent to a hoof!
- Act as a brace to add strength to our finger tips

Question 23

burns

Answer 23

• Causes rapid fluid loss and reduced blood flow
  
  • Infection risk is high

first, second, third degree

Question 24

first degree burn

Answer 24

○ Epidermis only

○ Sun burn, UV rays

Question 25

second degree burn

Answer 25

○ Destruction of tissue in the dermis
○ Blisters are often at the level of second degree and worse
○ Lots of vessels, sweat glands, leading to fluid loss
○ Concern for infection, because epithilial is there to protect the vessels.

Question 26

3rd degree burn

Answer 26

○ No protection
○ Blackening of tissue
○ Lost the abilitiy to repair the region because vessels are destroyed, fluid loss, severe risk of infection.

Question 27

cancer of epithelia

Answer 27

(Carcinoma)

• Fastest growing cancer in western hemisphere
• Name of carcinoma refers to “where” abnormal cell growth occurs

basal, squamous, melanoma

Question 28

basal cell

Answer 28

Karitinocytes, localised, not involving the melanocytes

Question 29

squamous cell

Answer 29

○ In stratus spinosum

○ Benign, localized

Question 30

melanoma

Answer 30

○ Localized to basal layer but involve melanocytes.
○ (4mm in size might be too late)
○ Asymmetrical
○ Often becomes malignant