Skin structure and function

Question 1

What function does the dermo-epidermal junction have?

Answer 1

support, anchorage, filtration

Question 2

What type of epithelium is the epidermis?

Answer 2

Stratified cellular epithelium (squamous?)

Question 3

What embrological layer does the epidermis come from?

Answer 3

Ectoderm

Question 4

Name some cells in the Dermis

Answer 4

Mainly fibroblasts. Macrophages, mast cells, lymphocytes, langerhands cells

Question 5

What embrological layer does the dermis come from?

Answer 5

Mesoderm

Question 6

What embrological layer do the melanocytes come from?

Answer 6

neural crest

Question 7

What is the periderm?

Answer 7

A single layer during embrology that creates the epidermis

Question 8

What are blaschkos lines?

Answer 8

Lines of growth of the skin

Question 9

What are keratinocytes?

Answer 9

Cells that contain keratin filaments. They make up most of the epidermis

Question 10

What are the four layers of the epidermis structure?

Answer 10

Keratin layer

Granular layer

Prickle cell layer

Basal layer

Question 11

How often does the epidermis renew?

Answer 11

every 28 days

Question 12

What are the prickle cells held together by to provide strength?

Answer 12

Desmosomes

Question 13

What is filaggrin?

Answer 13

Filament aggregating protein, aggregates the keratin for them to join together

Question 14

What is the keratin layer?

Answer 14

Keratin layer is made of corneocytes (which are overlapping non-nucleated cell remnants. It forms the insoluble cornified envelope. Forms a tight water proof barrier. DEAD LAYER.

Question 15

What are melanocytes?

Answer 15

Pigment producing cells that contain the organelle melanosome. The melanosome allowes the transport of melanin from melanocytes to keratinocytes through its dendritic arms

Question 16

How do melanocytes protect against sun damage?

Answer 16

They sit over the nuclei of the keratinocytes

Question 17

What are Langerhans Cells and where do they live?

Answer 17

They are found in epidermis, dermis, lymph nodes. In the epidermis they live in the prickle cell layer.

They are antigen presenting cells for immune defence

Question 18

What are Merkel cells and where are they found?

Answer 18

They are found in the basal layer of the epidermis.
They are touch receptors which respond to pressure

Question 19

What are the three part of the hair follicle?

Answer 19

Infundibulum - upper part
Isthmus - where sebaceous glands open up into follicle and where stem cells are located
hair bulb

Question 20

What is the pilosebaceous unit?

Answer 20

• hair follicle
• hair shaft
  -sebaceous gland
  -arrector pili muscle

Question 21

What are the three hair growth phases?

Answer 21

Anagen (growing phase)
Catagen (involuting phase)
Telogen (resting shedding phase)

Question 22

What is Lanugo hair?

Answer 22

Soft fluffy in utero hair

Question 23

What is vellus hair?

Answer 23

Normal hair

Question 24

What is Terminal hair?

Answer 24

Scalp, eyebrows, pubic

Question 25

What is the hyponychium in relation to the nail?

Answer 25

The bit under the nail, that holds the nail plate down.

Question 26

What is the dermo-epidermal junction made of?

Answer 26

proteins and collagen

Question 27

What are the three layers of the dermo-epidermal junction?

Answer 27

lamina lucida lamina densa sub-lamina densa zone

Question 28

Name some cells in the Dermis

Answer 28

Mainly fibroblasts. Macrophages, mast cells, lymphocytes, langerhands cells

Question 29

What cell makes collagen and elastin

Answer 29

Fibroblasts

Question 30

What are Pacinian corpuscles and Meissner's corpuscles

Answer 30

They are special receptors - nerves Pacinian corpuscles are special receptors for pressure (look like an onion) Meissner's corpuscles are special receptors for vibration.

Question 31

What is the matrix of the hair

Answer 31

The part where the hair is made

Question 32

What part of the hair shaft is the medulla?

Answer 32

The medulla is the innermost layer of the hair shaft.

Question 33

What part of the hair shaft is the cortex?

Answer 33

Cortex – middle layer of the hair shaft, contains the pigment and makes up most of the shaft structure

Question 34

What does the Sebcaseous gland do?

Answer 34

Produces sticky oil to lubricate hair follicle

Question 35

What does the aprocine gland do?

Answer 35

Discharges into hair follicle but unsure of purpose

Question 36

What does the Eccrine gland do?

Answer 36

Sweat gland for thermo-regualtion, and filtration