SKIN ANATOMY II

Question 1

where can’t we find hair?

Answer 1

palms, soles and lips

Question 2

what is hair made of?

Answer 2

dead, keratinised cells

Question 3

where is hair come from?

Answer 3

hair follicle and also projects from there

Question 4

the 2 accessories of a hair shaft are?

Answer 4

• arrector pili muscle
• root hair plexus - collection of sensory nerves at base of each hair follicle

Question 5

role of the arrector pili muscle?

Answer 5

contraction –> goose bumps –> improves insulation

Question 6

role of root hair plexus

Answer 6

heightened sensation

Question 7

what is sebum?

Answer 7

a oily secretion of sebaceous gland that nourishes hair shaft and naturally moisturises skin

Question 8

what acts as the water repellence of the skin?

Answer 8

sebum

Question 9

how is acne formed?

Answer 9

increase in sebum production + blocked hair follicles + infection

Question 10

2 types of sweat glands?

Answer 10

eccrine and apocrine

Question 11

eccrine is found in _____(1)_______ while apocrine is found in _____(2)________

Answer 11

(1): most areas of the skin
(2): specific areas like armpit, groin and around the nipples

Question 12

eccrine pours _____(1)______ and important in ____(2)_______, _____(3)_____ and ______(4)_______; whether apocrine secrete ____(5)_____ and influenced by ______(6)__________, e.g. _____(7)_____

Answer 12

(1): watery secretions directly onto skin surface
(2): thermoregulation
(3): excretion
(4): some antibacterial actions
(5): sticky/oily at times with potentially odorous secretion
(6): hormones
(7): lactation

Question 13

what are the 3 main functions of nails?

Answer 13

• protect fingetips/toes
• enhance sensation
• deformation

Question 14

what would aging affect the epidermis and dermis?

Answer 14

• thinner and drier epidermis –> less sebum
• thin dermis –> less collagen –> wrinkling and sagging

Question 15

how does aging affect thermoregulation?

Answer 15

aging –> reticular slower –> less blood flow –> less nutrients –> naturally healing impairments and less sweats

Question 16

why pale skin and grey hair are signs of aging?

Answer 16

less pigmentation

Question 17

how tobacco smoke causes premature skin aging?

Answer 17

• contains agents that accelerate aging
• damage collagen and elastin
  –> poor wound healing, acne, skin and oral cancers

Question 18

what effect nicotine has on skin?

Answer 18

reduces blood circulation in the dermis

Question 19

_____(1)_____ is found in the ______(2)_____ therefore it is not shed, on the other hand, ____(3)____ is found in the ______(4)______ so is shed with keratinocytes

Answer 19

(1): melanocytes
(2): stratum basale
(3): melanosomes
(4): epidermal cells

Question 20

melanin pigment absorbs _______, therefore protect cells from UV damage

Answer 20

UV light

Question 21

where is melanin produced?

Answer 21

melanocytes

Question 22

what is the role of melanosome?

Answer 22

vesicle containing melanin

Question 23

is the density of melanocytes varies throughout the body and through time?

Answer 23

yes

Question 24

compare mole vs freckle?

Answer 24

• mole: cluster of melanocyte - over-proliferation
• freckle: melanocytes overproducing melanosomes triggerd by sun exposure

Question 25

which vitamin is essential for normal calcium metabolism and strong bones?

Answer 25

vitamin D

Question 26

what does vitamin D deficiency cause?

Answer 26

rickets and affect mood

Question 27

which is required for vitamin D synthesis?

Answer 27

UV exposure

Question 28

explain a greater incidence of lightly pigmented skin and higher latitudes and darker pigmented at certain part of the Earth?

Answer 28

• closer to equator –> more sun exposure –> mote UV –> skin produces more melanin
• higher pigmented people susceptible to vitamin D deficiency particularly at extreme latitudes

Question 29

which layer should tattoo be inserted into the skin for it to be permanent?

Answer 29

• dermis layer
• not shed
• captured but not broken down inside immune cells/scar tissue

Question 30

why can we feel pain during tattoo?

Answer 30

dermal layer containing pain receptors and free nerve endings

Question 31

basal melanoma originates in ________(1)________ whereas malignant melanoma originates in _______(2)______

Answer 31

(1): stratum basale
(2): melanocytes

Question 32

which one is more common and mild between basal and malignant melanoma?

Answer 32

basal melanoma

Question 33

if ______(1)_______ melanoma locates in _______(2)________ layer, it would be more dangerous and even highly metastatic, especially when associated with depth, explain why?

Answer 33

(1): malignant
(2): dermis
- dermis contains blood vessels and lymphatic drainage pipes, if the tumour spreaded into the blood vessel, in would be transferred to other parts of the body which makes it highly metastic and deadly if not treated