EC Hair Growth and Follicle Anatomy Flashcards

Which phase of the hair growth cycle is the active growth phase during which electrolysis is most effective?

Answer: Anagen

The anagen phase is the active growth phase when the hair follicle is most vulnerable to permanent destruction by electrolysis.

What is the name of the innermost layer of the hair shaft?

Answer: Medulla

The medulla is the innermost layer of the hair shaft, though it may be absent in fine hair types.

Which structure at the base of the hair follicle contains the actively dividing cells responsible for hair growth?

Answer: Hair bulb matrix

The hair bulb matrix contains the rapidly dividing keratinocytes that produce the hair shaft.

During which hair growth phase does the follicle shrink and detach from the dermal papilla?

Answer: Catagen

The catagen phase is a transitional period during which the follicle regresses and the hair stops growing.

What percentage of scalp hairs are typically in the telogen (resting) phase at any given time?

Answer: 15–20%

Approximately 15–20% of scalp hairs are in the telogen resting phase at any given time.

Which skin layer houses the hair follicle bulb and dermal papilla?

Answer: Dermis

The dermis contains the hair follicle bulb and the dermal papilla, which supplies blood and nutrients for hair growth.