Parts of the Hair
Trichology is the scientific study of ____, including its care and disorders.
Hair
The hair shaft consists of ____ main layers.
3
Healthy hair on the scalp grows about ____.
1/2 inch per month
Hair texture is measured by the diameter of the hair strand and is classified as coarse, ____, or fine.
medium
The hair’s ____ is its ability to absorb moisture.
porosity
The main component of hair is a ____ called keratin.
Protein
Hair’s natural tendency to flow to one side is called the ____.
Hair stream
____ are made up of amino acids.
Proteins
Hair with a ____ texture has the largest diameter.
coarse
Alopecia is the technical term for ____.
abnormal hair loss
The part of the hair that extends above the skin surface is the ____.
Hair shaft
The cortex is the ____ layer of the hair.
middle
Black and brown hair colors are provided by ____.
eumelanin
Blonds have approximately ____ hairs on the head.
110,000
Pseudofolliculitis barbae is referred to as “_____.”
razor bumps
The portion of the hair that is enclosed within the follicle is the ____.
Hair root
The ____ glands secrete sebum.
sebaceous
The three different types of ____ bonds are hydrogen, salt, and disulfide.
side
Vellus or lanugo hair is ____ and appears nearly everywhere on the body.
short and fine
Dandruff is technically known as ____.
pityriasis
The chemical composition of average hair is ____ percent carbon.
51
Protein makes up ____ percent of hair.
91
Natural hair color is the result of the ____ pigment found within the cortex.
melanin
During the ____ phase, the hair is shed.
telogen
____ is caused by loss of natural melanin.
Canities