Anatomy of a Hair Flashcards
What is the other name for a hair?
Pili.
What is the main component that makes up the Hair?
The hair is composed of “Dead Keratinized cells” bonded together by extracellular proteins.
What is the portion of the Hair called that projects through the surface of the skin?
This is named the shaft.
What is the portion of the Hair the penetrates into the Dermis and sometimes into the Subcutaneous layer?
This is the Root of the Hair.
What are the 3 concentric layers of cells in the Shaft and Root of the hair?
Consisting of “Medulla, Cortex and Cuticle”.
What does a lack of pigment in hair mean?
This means the Medulla contains air bubbles in white hair. and in grey hair the melanin isn’t being created.
What is the part of the Hair that forms a large part of the shaft and what does it consist of?
The Cortex forms a large amount of the Shaft and is made up of Elongated cells.
What are the flat cells that are the most heavily Keratinized?
These are the cells of the Cuticle in the hair.
Where is the Cuticle of the hair located?
This is the most outer layer.
What is the part of the Hair surrounding the Root?
This is the Hair Follicle.
What makes up the Epithelial root sheath?
The External and Internal root sheath.
What is the External root sheath?
This is a Downward projection Continuation of the Epidermis.
What is the Internal root sheath?
This is produced by the matrix and forms a cellular tubular sheath of epithelium between the external root sheath of the hair.
What holds the nipple shaped portion of the hair?
The Hair bulb.
What does the hair bulb consist of?
The Hair bulb houses:
A nipple shaped indentation called “papilla of the hair” this is consisted of Areolar connective tissue and many blood vessels that nourish the hair growth.
And a layer of cells called the “Hair matrix” they are responsible for the growth of existing hairs.
