integumentary system Flashcards
1
Q
What are the main cell types of the Epidermis?
A
- Keratinocytes: main cell type, produce keratin, found deep in epidermis
- Melanocytes: produce melanin (pigment), found deepest in epidermal layer
- Merkel cell: specialised sensory cell, responds to light/ touch
- Dendritic cell: ingests invading pathogens/ foreign materials, activates immune defences of the body
2
Q
What are the epidermal layers?
A
- Stratum corneum: cells become more squamous, become dead and fall away
- Stratum granulosm- keratin starts to be layered down
- Stratum spinosum: cells begin to change
- Stratum Basale: dividing stem cells that create daughter cells and gradually move up through skin.
3
Q
What does the dermis contain?
A
- Collagen fibres
- Nerve endings
- Sweat glands
- Blood vessels
- Hair follicles
- Elastic fibres
4
Q
What are the two dermal layers?
A
Papillary & reticular layer
5
Q
What are the dermal papillae?
A
They are located between epidermis and dermis and help increase surface area for nutrient exchange, contribute to sensory perception and regulate hair growth by interacting with hair follicles.
6
Q
What are the 4 skin functions? Briefly describe each one
A
- Protection- Infection, dehydration and chemical resistant layer, physical damage- melanocytes protecting against UV.
- Temperature regulation- Eccrine sweat glands come to surface, hypothalamus senses temp changes and can cause vasodilation of blood vessels.
- Secretion- sebaceous glands are associated with hair follicles and create sebum which is oily and secretes oil.
- Cutaneous sensation- free nerve endings have a role in sense of touch.
7
Q
What are three signs of non-verbal communication?
A
- Body odour/ stress
- Blushing
- Pheromones
8
Q
What can skin colour be affected by?
A
- Haemoglobin
- Melanin
- Carotene
9
Q
What is abnormal colouration?
A
- Cyanosis
- Jaundice
- Albinism
- Haematoma
10
Q
What are the stages of scaring of the skin?
A
- Fibroblasts lay down a framework of fibres to damaged tissues.
- Irregular arrangement.
- Sweat glands/ hair follicles don’t regenerate
- Irregular framework- different pattern of blood vessels.