HAIR

1. Amino Acids

1.1. Primarly made up of proteins

1.2. link together to become protein chains that form the cortex

2. Structure of Hair

2.1. Hair Follicle

2.1.1. Tube-like depression or pocket in skin or scalp that contains the hair root.

2.2. Dermal Papilla

2.2.1. small cone-shaped elevation at base of the hair follicle that fits into hair bulb

2.3. Hair Bulb

2.3.1. lowest part of a hair strand

2.4. Arrector Pili Muscle

2.4.1. small, involuntary muscle in base of the hair follicle.

2.4.2. Causes the hair to stand on end when a person is scared or cold

2.5. Sebaceous Gland

2.5.1. oil glands in skin connected to hair follicles.

2.5.2. Prevents the hair and skin from becoming too dry

3. Structure of Hair Shaft

3.1. Cuticle

3.1.1. outermost layer of the hair

3.2. Cortex

3.2.1. middle layer of the hair composed of round cells

3.3. Medulla

3.3.1. innermost layer of the hair composed of round cells

3.4. Macrofibrill

3.5. Microfibrill

3.6. Protofibrill

4. Two Primary parts of the hair

4.1. Hair Root

4.1.1. : Portion of hair inside the hair follicle under the skin’s surface

4.2. Hair Fiber

4.2.1. portion of the hair that extends above skins surface

5. Keratinization

5.1. process of cells changing their shape, drying out and forming kerinat protein

5.2. Once keratinized, the cells that form the hair fiber or strand are longer alive