Science: Hair Theory

Question 1

What is Trichology?

Answer 1

The study of hair

Question 2

Only cells in the hair ________ are alive.

Answer 2

bulb

Question 3

Hair grows from a tube-like “pocket” called a root sheath or a ___________?

Answer 3

follicle

Question 4

The follicle for straight hair will be what shape?

Answer 4

round or oval

Question 5

The hair follicle for wavy to curly hair is what shape?

Answer 5

More oval

Question 6

The hair follicle for tightly curled hair is what shape?

Answer 6

flattened, elliptical

Question 7

What is the portion of hair inside the hair follicle under the skin’s surface?

Answer 7

hair root

Question 8

What is the portion of hair that extends above the skin’s surface?

Answer 8

Hair fiber

Question 9

Located at the bottom of the follicle and supplying nourishment to the germinal matrix is the…..
a. tube
b. base
c. papilla
d. medulla

Answer 9

c. papilla

Question 10

What are the 3 major layers of hair?

Answer 10

Cuticle- outer covering
Cortex- Second layer
Medulla- central core

Question 11

What produces sebum to prevent hair and skin from becoming too dry?

Answer 11

Sebaceous (oil) glands

Question 12

What mixes with perspiration to form the acid mantle on hair?

Answer 12

Sebum (oil)

Question 13

What protects the cuticle of hair fiber and maintains the natural pH of hair and skin?

Answer 13

Acid Mantle

Question 14

What causes hair to stand on end when a person is scared or cold?

Answer 14

Arrector Pili Muscle

Question 15

Hair pulled out from the roots will grow again unless the ___________ is destroyed.

Answer 15

papilla

Question 16

What is Keratinization?

Answer 16

Process of cells changing shape, drying out, and forming keratin protein

Question 17

What stage of hair growth is the active growing stage, during which time each hair bulb has an attached root sheath?

Answer 17

Anagen

Question 18

On average 90% of a person’s hair is in the anagen stage. How long does this stage last?

Answer 18

2-6 years

Question 19

Which stage of hair grown is a brief transitional stage, when all cell division stops?

Answer 19

Catagen

Question 20

How long does the catagen stage last?

Answer 20

a few weeks

Question 21

Which stage of hair growth is the resting stage, when each hair bulb has no attached root sheath.?

Answer 21

Telogen

Question 23

How long does the telogen stage last?

Answer 23

3-4 months

Question 24

Hair growth can be affected by?

Answer 24

illness, lack of vitamins and minerals, disease, medication

Question 25

In humans, the average rate of hair growth is ?

Answer 25

1/2" per month

Question 26

Eyebrows and eyelashes are replaced every:

Answer 26

4-5 months

Question 27

3 factors that affect the behavior of hair:

Answer 27

heredity environment/weather products or appliances

Question 28

Higher cuticle/cortex ratio = more resistant or easily molded?

Answer 28

more resistant

Question 29

Lower cuticle/cortex ratio = more resistant or easily molded?

Answer 29

easily molded

Question 30

A pigment called _________ gives skin and hair their color.

Answer 30

melanin

Question 31

In what part of the hair is melanin mostly found?

Answer 31

the cortex

Question 32

Eumelanin is a type of melanin responsible for what color?

Answer 32

brown/black

Question 33

Pheomelanin is a type of melanin responsible for what color?

Answer 33

red/yellow

Question 34

What is the term for the total lack of pigmentation in hair and skin?

Answer 34

albinism

Question 35

Gray hair is caused by reduced color pigment in the _________ layer of the hair.

Answer 35

cortex

Question 36

People with lighter hair color have melanin only in the __________. cortex, cuticle, or medulla

Answer 36

cortex