Chemical Composition
The tiny grains of pigment in the cortex that give natural color to hair.
MELANIN
Oil glands of the skin that secrete an oily substance called sebum, which lubricates the hair and skin.
SEBACEOUS GLANDS
The outermost layer of the hair
Cuticle
Units of structure that build proteins.
AMINO ACIDS.
The spiral shape created when polypeptide chains intertwine with each other
Helix
___________ ______________ hair often has low elasticity, breaks easily, and has a tendency to knot on the ends.
Extremely curly
A minute, involuntary muscle fiber in the skin inserted in the base of the hair follicle. "goose bumps"
ARRECTOR PILI
Innermost layer; also referred to as the pith of the hair. It is composed of round cells.
Medulla
Chemical bonds that link two amino acids.
Peptide (or end) bonds
Weak, temporary cross-links that can be broken by changes in pH or by strong alkaline or acidic solutions
SALT BONDS
Wave patterns are the result of _________________ and ______________background, although straight, wavy, and extremely curly hair exist in all races.
genetics and racial background
The tubelike depression, or pocket, in the skin or scalp that contains the hair root.
FOLLICLE
The middle layer of hair; a fibrous protein core formed by elongated cells containing melanin pigment. About 90 percent of hair weight comes from the cortex.
Cortex
Physical side bonds that are easily broken by water or heat.
HYDROGEN BONDS
Strong chemical bonds that join the sulfur atoms that can be broken by permanent waves.
DISULFIDE BONDS
The spiral shape created when polypeptide chains intertwine with each other
Helix
the thickened, club-shaped structure that forms the lower part of the hair root
Hair Bulb
It consists of a single layer of transparent, scalelike cells that overlap like shingles on a roof. A healthy, compact _________ layer is the hair’s primary defense against damage.
Cuticle
What are the 5 elements in the hair shaft and how much % is in each.
•Carbon – 51 percent
•Oxygen – 21 percent
•Hydrogen – 6 percent
•Nitrogen – 17 percent
•Sulfur – 5 percent
A long chain of amino acids linked by peptide bonds. They intertwine with each other in a spiral shape called a helix
Polypeptide chain
___________: Provides brown and black color to hair.
___________:Provides natural hair colors from red and ginger to yellow-blonde tones.
Eumelanin and Pheomelanin
A small, cone-shaped elevation located at the base of the hair follicle that fits into the hair bulb; contains the blood and nerve supply that provides the nutrients needed for growth.
Dermal Papilla
_____________ Structure located in the cortex provide hair elasticity
Protein
The process during which newly formed cells in the hair mature; they fill up with keratin, move upward, lose their molecules, and die.
KERATINIZATION
List the side bonds found in the hair protein structure:
Hydrogen, Salt, Disulfide