CPE Anatomy & Physiology of Hair Growth

Question 1

What part of the hair contains the living cells responsible for growth?

Accepted Answer

Hair bulb

Answer

The hair bulb is the expanded, club-shaped structure at the base of the hair follicle, where the hair shaft originates. It contains the dermal papilla, which supplies nutrients, and the matrix cells. These actively dividing living cells are responsible for producing new hair cells and driving the entire process of hair growth.

Question 2

Which layer of the hair is responsible for its color?

Accepted Answer

Cortex

Answer

The cortex is the thickest and most significant layer of the hair shaft, located between the outer cuticle and the innermost medulla. This layer contains melanin, the pigment that determines the hair's natural color. Beyond color, the cortex also provides the hair with its strength, elasticity, and overall texture.

Question 3

What is the term for the hair growth phase?

Accepted Answer

Anagen

Answer

The anagen phase is the active growth stage of hair, where cells in the hair bulb rapidly divide, pushing the hair shaft upwards and out. During this phase, hair follicles are actively producing new hair, and this stage can last for several years, determining the maximum length of hair.

Question 4

What is the function of the hair papilla?

Accepted Answer

Supply nutrients and oxygen

Answer

The hair papilla is a small, cone-shaped indentation at the base of the hair follicle, containing blood vessels and nerves. Its primary function is to supply the hair matrix cells with essential nutrients and oxygen, which are crucial for cell division and the continuous growth of the hair shaft. Without the papilla, hair growth would cease.

Question 5

What causes hair to grow?

Accepted Answer

Answer

Hair growth is fundamentally caused by the rapid and continuous division of specialized cells within the hair matrix, located in the hair bulb at the base of the follicle. As these new cells are produced, they push older cells upwards, which then harden and die through a process called keratinization, forming the visible hair shaft. This constant cell proliferation is what extends the hair from the scalp.

(CPE) Certified Professional Electrologist Practice Test

(CPE) Certified Professional Electrologist Practice Test

CPE Anatomy & Physiology of Hair Growth