structure of skin and accessory structures

Question 1

Integumentary system.
what are the 6 general functions?
TBPCSE

Answer 1

Thermoregulation

blood reservoir

protection

cutaneous sensations

synthesis of vitamin D

excretion / absorption

Question 2

structure of skin. what re the two layers of skin?

Answer 2

Epidermis - superficial

dermis - deeper

Question 3

Epidermis.
structure and 4 types?
KMLM

Answer 3

keratinised stratified squamous epithelium

Keratinocytes

melanocytes

langerhans

merkel

Question 4

stratum basale (epidermis)

Answer 4

deepest layer

single row of cuboidal / columnar keratinocytes

Question 5

stratum spinosum (Epidermis)

Answer 5

superficial to stratum basale

8-10 layers of thorn keratinocytes

Question 6

stratum granulosum (epidermis)

Answer 6

superficial to stratum spinosum

3-5 layers of flattened keratinocytes

Question 7

stratum lucidum (epidermis)

Answer 7

superficial to stratum granulosum

present only in thick skin

Question 8

stratum corneum (epidermis)

Answer 8

25-30 layers of flattened thin overlapping dead keratinocytes

Question 9

Define keratinisation

Answer 9

replacement of keratinocyte contents with protein keratin as moved from one epidermal layer to next

Question 10

Dermis. what 2 regions and 2 structure facts

Answer 10

deeper layer of skin
composed of dense irregular CT

papillary region
reticular region

Question 11

Papillary region (dermis)

Answer 11

top 20% of dermis

thin and fine collagen and elastic

Question 12

reticular region (dermis)

Answer 12

bottom 80%
dense irregular CT
this and coarse collagen and elastic

Question 13

3 accessory structures of skin

Answer 13

hair
glands
nails

Question 14

Hair (pili)
3 structure
3 function

Answer 14

shaft
root
composed of red keratinised epidermal cells

prevent heat loss
protection
sense light touch

Question 15

skin glands. name 3 types

Answer 15

sebaceous (oil)
sudoriferous (sweat)
ceruminous (wax)

Question 16

oil glands (sebaceous)

3 structure
3 function

Answer 16

opens into hair follicle
absent in palms
secreting portion in dermis

produce sebum
prevent hair from drying out
keeps skin set and pliable

Question 17

sudoriferous (sweat) glands
2 types

3 structure
3 function

Answer 17

eccrine
secretory portion in deep dermis
excretory portion onto epidermis
most region of skin

produce clear sweat
regulate body temp
waste removal

apocrine
axilla, groin, areolar
excretory portions opens to hair follicle
secretory portion in deep dermis and hypodermics

milky sweat
onset puberty
stimulated emotional stress and sexual excitement

Question 18

ceruminous (wax) glands
3 structure
3 function

Answer 18

modified sweat gland
located external ear
secretory portion in hypodermis

produce cerumen (wax)
waterproof canal
prevent microbes from entering cells

Question 19

Nails
2 structure
3 function

Answer 19

plates of tightly packed hard dead keratinised epidermal cells
nail body, free edge, nail root

protection
grasping objects
enhance touch perception

Question 20

Epidermal wound healing

5 steps

Answer 20

basal cells break contact with basement membrane

cells enlarge and migrate over wound

once met, stop migrating (contact inhibition)

epidermal growth factor leads to basal set cells to divide and replace ones moved into wound

relocated cells divide to build new state - thickening new epidermis

Question 21

Deep wound healing

4 phases & brief description of each

IMPM

Answer 21

inflammatory

• blood clot wound edges
• epic cells migrate across wound
• vasodilation

Migratory

• regret of epidermal cells
• clot leads to scab
• formation of scar

Proliferative
- migratory phase intensity

Maturation

• scab comes off
• epidermis back to normal thickness
• fibroblasts disappear
• blood vessels back to normal