Parts of the Hair
What is the outermost layer of hair?
hair cuticle
What measurement describes the number of individual hair strands on 1 square of the scalp?
density
What are hydrogen bonds reformed by?
drying or cooling
What is the phase in which the hair can shed?
telogen phase
Can wave patterns vary around the head?
yes
What two parts make up a strand of human hair?
the root and the shaft
What ability of the hair absorbs moisture?
porosity
What are salt bonds broken by?
changes in pH
What is the phase in which the follicle canal shrinks and detaches from the dermal papilla?
catagen phase
by using a shampoo that helps return the scalp to its natural pH
What is the hair's pith or core?
medulla
What is the hair's ability to stretch and return to its original length without breaking?
elasticity
What is a polypeptide chain?
a long chain of amino acids linked by peptide bonds
What is the anagen phase?
the phase in which new hair is produced
What causes dry hair and scalp?
inactive sebaceous glands
What structure surrounds the hair root and anchors the hair of the skin?
the hair bulb
What determines the hair texture?
the diameter of an individual hair strand
When should a cosmetologist allow the hair to cool before styling?
when hydrogen side bonds have been broken by heat
What are the three growth cycles of hair?
anagen, catagen, and telogen
What is a wave pattern?
the amount of movement or shape of the hair strand
Which part of the hair root supplies nutrients that helps the hair grow?
the dermal papilla
What is hair with high porosity like?
it has a raised cuticle and is usually damages, dry, fragile, and brittle
What chemical elements make up human hair?
carbon, oxygen, hydrogen, nitrogen, and sulfur
What is the only way for your hair to grow back fast?
genetics
What are the three hair growth patterns?
hair stream, whorl, and cowlick