Fill in the blanks: The portion of the hair that projects from the surface of the skin is the____, and the portion within the dermis is the ___, which is embedded in a(n)_____ . The portion of the hair that contains cells that undergo mitosis during the growth stage of the hair is known as the                    .

Which of the following is not a function of body hair in humans?

a. Protection from the environment

b. Sensation

c. Protection from mechanical trauma

d. Regulation of blood flow

Why don't you bleed when you cut your nails? Why don't you bleed when a hair is pulled?

Manufacturers of shampoos and conditioners often claim their products contain vitamins that are necessary to keep hair shafts healthy. Do hair shafts need vitamins? (Hint: Vitamins are required for cells to carry out certain reactions.) Why or why not? How valid are these claims?

The hair and nails are sometimes called accessory organs. Are these structures technically organs? Why or why not?