Skin

Question 1

What is the intergumentary system made up of?

Answer 1

skin, hair, nails, glands and sensory receptors

Question 2

What are the two types of skin on the body?

Answer 2

Hairy and Glabrous

Question 3

What are the 4 functions of skin?

Answer 3

• Protection
• Thermoregulation
• Humidity control
• Produces vitamin D

Question 4

What is the epidermis?

Answer 4

Outer layer of skin with no blood vessel supply
Also contains melanocytes, Merkel cells and Langerhans cells
30-45 days for basal cells to mature and migrate to top of epidermis

Question 5

What are the 5 layers of the epidermis?

Answer 5

• Stratum corneum
• Stratum lucidum
• Stratum granulosum
• Stratum spinosum
• Stratum basale

Question 6

What are the two parts of the dermis?

Answer 6

• Papillary (20%) mostly loose connective tissue
• Reticular (80%) dense irregular connective tissue

Question 7

What are the 6 cells in the epidermis?

Answer 7

• Fibroblasts and keratinocytes
• Macrophages: immunity
• Adipocytes: fat cells
• Mast cells: wound healing
• Myofibroblasts:
• Myoepithelial cells: sweat glands

Question 8

What are keratinocytes?

Answer 8

Make up more than 90% of the cells in the epidermis
Essential for forming protective barrier

Question 9

What are Desmosomes?

Answer 9

• Connect cells to each other
• provide strength

Question 10

What are Lamellar granules?

Answer 10

• Produced by keratinocytes
• Round/ oblong in shape
• Secretory organelles required for desquamation
• help form the impermeable lipid-containing barrier

Question 11

What is keratin?

Answer 11

• a major component of the cytoskeleton
• Network of fibre bundles
• Bundles composed of keratin make coils
• Contribute to the structural integrity

Question 12

What are hemi-desmosomes?

Answer 12

• connect keratinocytes to the basement membrane
  receptors and contribute to strength
• Loss can again lead to skin blistering

Question 13

What are the melanocytes?

Answer 13

Produce melanin and protects against UV radiation while supporting the immune system.
Found in bottom layer of epidermis.

Question 14

What are langerhans cells?

Answer 14

also known as dendritic cells and contain Birbeck granules
Found throughout epidermis and support immune system.

Question 15

What are merkel cells?

Answer 15

oval-shaped and responsible for light touch and sensation through their connection to nerve fibres.

Question 16

What is hyperpigmentation?

Answer 16

• Discoloured or darkened skin caused by increased melanin production
• treatment with photoprotection to prevent new spots or melanin inhibitors

Question 17

What is allodynia?

Answer 17

• Hypersensitivity to touch which can manifest as a type of neuropathic pain
• Everyday tasks become difficult
• Caused by diabetes, fibromyalgia, migraines etc

Question 18

What is langerhan cell histiocytosis?

Answer 18

• Buildup of excess immature Langerhans cells form tumours in the skin, unknown cause
• Cancer?
• Rare (1 in 5 million)
• Can severely affect the immune system and even be fatal)

Question 19

What is the anatomy of the nail?

Answer 19

• Nail body formed on the nail bed
• Lunula: Crescent shape at the base of the nail
• Keratin-rich and densely packed dead keratinocytes
• For protection

Question 20

What are the 4 types of glands in the skin?

Answer 20

sudoriferous glands
sebaceous glands
ceruminous glands
mammary glands

Question 21

What are the three ways of secretion?

Answer 21

• Merocrine- most common. Excretion via exocytosis
• Apocrine- cell membrane buds off into the duct
• Holocrine- cell membrane ruptures to release the product

Question 22

What are sudiferous glands?

Answer 22

Sweat glands
- Eccrine (surface of skin)
- Apocrine (hair follicles)

Question 23

What are sebaceous glands?

Answer 23

Oil-producing glands that release sebum into follicular duct

Question 24

What are ceruminous glands?

Answer 24

apocrine glands found in the external auditory canal
produce ear wax
protective role
1000-2000 ceruminous glands in a normal ear

Question 25

What are mammary glands?

Answer 25

Type of apocrine gland
Production of milk after birth
Each weighs 500-1000g

Question 26

What are mechanoreceptors?

Answer 26

Respond to physical changes
Meissner’s corpuscle: indentation and slipping
Pacinian corpuscle: vibrations
Merkel’s disk: texture
Ruffini corpuscle: stretch

Question 27

What are thermoreceptors?

Answer 27

Body has both cold receptors and warm receptors
When changes in temperature occur, the opposite receptor stops discharging

Question 28

What are nociceptors?

Answer 28

• Signal pain related to pressure, temperature and chemicals
• triggered by tissue damage

Question 29

What is atopic dermatitis?

Answer 29

Chronic, recurrent and inflammatory disease of the skin
Affects both children and adults

Question 30

How does the skin repair wounds?

Answer 30

• Haemostasis: platelet aggregation to stop bleeding
• Inflammation: Influx of cells begin inflammatory process
• Proliferation
• Maturation

Question 31

What are three means of transdermal drug delivery?

Answer 31

Intercellular: In between cells
Intracellular: Through cells
Follicular: Through hair follicles

Question 32

What is the bricks and mortar model of the skin?

Answer 32

• Bricks: Corneocytes
• Mortar: Lipid matrix

Question 33

What are the 6 active delivery methods?

Answer 33

• Iontophoresis: moving ions
• Sonophoresis: ultrasound
• Electroporation: creating pores using electric impulses
• Photomechanical waves: using photodynamic waves to penetrate
• Microneedle
• Thermal ablation: localised heat to create microchannels

Question 34

What is an ITS?

Answer 34

Iontophoretic transdermal system

Question 35

What are the 3 passive delivery systems?

Answer 35

Vesicles: water-filled particles with a bilayer to carry drugs
Polymer nanoparticles
Nanoemulsion: a mixture of oil and water

Question 36

What is regenerative medicine?

Answer 36

Isolation of cells in lab
Once desired cell number is reached, biocompatible material is combined
Cell and scaffold material stimulated in lab until mimics the tissue
Reintroduced to patient