Skin

Question 0

5 functions of skin

Answer 0

Protection
Thermoregulation
Excretion of sweat
Vit D synthesis
Sensory reception

Question 1

Name 3 skin appendages

Answer 1

Glands
Hair
Nails

Question 2

What is the epidermis made of?

Answer 2

Stratified keratinised squamous epithelium

Question 3

What is the top layer of the epidermis called?

Answer 3

Stratum corneum

Question 4

Name the 4 layers of the epidermis in order

Answer 4

Stratum basale
Stratum spinosum
Stratum granulosum
Stratum corneum

Question 5

Which layer of the epidermis is the thickest?

Answer 5

Stratum spinosum

In hard skin the stratum corneum is thick though

Question 6

Why do cells of the stratum spinosum appear spikey?

Answer 6

They are attached by desmosomes

Question 7

Describe the stratum basale

Answer 7

Attached to basement membrane
Stem cells of the epidermis
Cuboidal epithelial cells

Question 8

What is the extra layer of the epidermis only found in thick skin?

Answer 8

Stratum lucidum
Between granulosum and corneum
Clear layer of cells

Question 9

Function of melanocytes

Answer 9

Produce pigment
Scattered in stratum basale
Melanin helps protect DNA from UV damage

Question 10

Function and location of merkel’s cells

Answer 10

Mechanoreceptors

Scattered in stratum basale

Question 11

Function and location of langerhans cells

Answer 11

Immunological function (antigen presenting and phagocytic)
Derived from bone marrow
Scattered in stratum spinosum and granulosum

Question 12

How thick is the epidermis?

Answer 12

70-600 micrometers thick

Question 13

What is the dermal Epidermal junction called?

Answer 13

Rete ridge system
Epidermal ridges
Dermal papillae

Question 14

Function of dermis

Answer 14

Binds epidermis to subcutaneous tissue through dense irregular CT
Support& tensile strength
Thermoregulation and epidermal nutrition

Question 15

Name the two layers of the dermis

Answer 15

Papillary layer (thin top layer)
Reticular layer (thick under layer)

Question 16

What does the papillary layer contain?

Answer 16

Fine interlacing collagen and elastic fibres

Small blood vessels (nourish epidermis, Thermoregulation)

Question 17

What does the reticular layer contain?

Answer 17

Thick irregular bundles of collagen
Coarse elastic fibres
Deep vascular plexuses

Question 18

Function of hypodermis

Answer 18

Attached skin to underlying structures and allows movement

Insulation and energy storage

Question 19

What is found in the hypodermis

Answer 19

Adipose tissue and loose CT

Major blood vessels, nerves, nerve endings and terminal parts of skin appendages

Question 20

What is hair?

Answer 20

Keratinised outgrowth of the hair follicle

Question 21

What is the hair bulb?

Answer 21

Terminal dilation of germinative cells that surround the DERMAL PAPILLAE

Question 22

What cells are found in the germative layer?

Answer 22

Stem cells and melanocytes

Question 23

What does the dermal papillae of a hair follicle contain?

Answer 23

CT containing blood vessels

Question 24

What are the arrector pili (what are they innervated by?)

Answer 24

Smooth muscle cells Lie obliquely and attatch hair follicle to CT of dermis Sympathetic nerves

Question 25

What sweat glands are found throughout the body?

Answer 25

Eccrine sweat glands Merocrine secretions of sweat Simple coiled tubular glands

Question 26

What type of epithelium are found in eccrine sweat glands?

Answer 26

Simple cuboidal and myoepithelial cells in distal secretory segment Stratified cuboidal epithelium in duct segment

Question 27

Sebaceous glands are located where? Function?

Answer 27

Branched acinar glands found between hair follicle and arrector pili muscle Holocrine secretion of sebum

Question 28

Function of sebum | How does acne happen?

Answer 28

Protective and waterproofing | If sebaceous glands are blocked and inflamed-> acne

Question 29

How to apocrine sweat glands differ from eccrine?

Answer 29

``` Located more deeply in dermis Wider lumens Associated with hair follicles Influenced by sex hormones- pheromones? Only found in areola axilla anal and genital regions ```