Question

A human head hair is best characterized by: a. The absence of a cortex. b. Its scale pattern. c. A medulla that is more than 1/2 the overall diameter of the hair shaft. d. A medulla that is absent or is less than 1/3 the overall diameter of the hair shaft.

Answer 1

d. A medulla that is absent or is less than 1/3 the overall diameter of the hair shaft is the correct answer.

Step-by-step explanation:

• A human head hair is best characterized by a medulla that is absent or is less than 1/3 the overall diameter of the hair shaft.

• Hair is a protein thread that develops from the follicles located within the dermis.

• Hair present on the head acts as a source of insulation, protect from the ultraviolet radiation and dust.

Hair consists of two different parts

• Follicle

• Hair shaft

hair shaft consists:

• cortex: located between hair cuticle and medulla

• cuticle cells: are the outermost portion of the hair shaft.

• medulla: is the inner layer of the hair.