Topic 9: Integumentary System - Epidermal Derivatives (Hair + Nails) Flashcards
1
Q
What are epidermal derivatives?
A
All derived (formed) from the epidermis
2
Q
Name 3 types of epidermal derivatives
A
- hair
- nails
glands
3
Q
What type of cells is hair made from?
A
- dead cells
4
Q
Name the 3 parts of hair
A
- root
- shaft
- hair follicle
5
Q
What is the hair root?
A
- dead cells below the surface of the skin
6
Q
What is the hair shaft?
A
- above the skin surface
7
Q
What is the hair follicle?
A
- surrounds the root
8
Q
Name the 3 parts to a hair follicle
A
- epithelial root sheath
- bulb
- hair matrix
9
Q
What is the epithelial root sheath?
A
- several epidermis layers extend into the dermis
10
Q
What is the bulb?
A
- expanded region at base of root
11
Q
What is the hair matrix? (2)
A
- single layer of cells (derived from basale cells)
- site of hair growth and melanin for hair colour
12
Q
What parts are associated with each hair follicle? (5)
A
- The outer CT sheath
- Hair papilla
- root hair plexus
- sebaceous gland
- arrector pili
13
Q
What is the purpose of the outer CT sheath? (2)
A
- holds follicle in place
- formed from the dermis
14
Q
What is hair papilla? (3)
A
- extends upwards beneath matrix
- contains blood supply for growing hair
- formed from dermis
15
Q
What is hair root plexus?
A
- free nerve ending (touch)
