Hair and Scalp Properties

All of the following are living portions of hair that are below the skin surface EXCEPT

• a. the hair bulb

• b. the arrector pili muscle

• c. the hair follicle

• d. the dermal papilla

What are the two parts of a strand of human hair?

• a. the root and the shaft

• b. the follicle and the bulb

• c. the dermal papilla and the arrector pili

• d. the cuticle and the cortex

Which part of the living portion of the hair is defined as the structure in the skin or scalp that surrounds the hair root and anchors the hair in the skin?

• a. the dermal papilla

• b. the hair bulb

• c. the arrector pili muscle

• d. the hair follicle

Which portion of the hair root structure supplies nutrients so that the hair can grow?

• a. the hair bulb

• b. the dermal papilla

• c. the arrector pili

• d. the hair follicle

Each of the following is a layer of the hair shaft structure EXCEPT ______.

• a. the cortex

• b. the hair fiber

• c. the hair cuticle

• d. the medulla

Which sentence best describes the medulla?

• a. The medulla is the hair’s outermost layer.

• b. The medulla is a cone-shaped elevation at the base of the hair bulb.

• c. The medulla is the hair’s pith or core.

• d. The medulla is the fibrous protein layer of the hair.

Which layer of the hair shaft provides strength, elasticity, and color?

• a. the hair cuticle

• b. the hair fiber

• c. the medulla

• d. the cortex

What are the major chemical elements that make up human hair?

• a. carbon, oxygen, hydrogen, nitrogen, and sulfur

• b. proteins, water, lipids, and traces of minerals

• c. amino acids and polypeptide chains

• d. hydrogen bonds, side bonds, and salt bonds

Which of the following best describes how a disulfide bond in human hair is formed?

• a. Oppositely charged atoms in the hair are attracted to one another to form weak physical cross-link side bonds.

• b. Amino acids are chemically bonded to each other, end to end, to form a polypeptide chain.

• c. Oppositely charged atoms are attracted to each other to form cross-linked side bonds between adjacent polypeptide chains.

• d. Sulfur atoms on neighboring cysteine amino acids within polypeptide chains in the hair join.

Which of the following is a situation in which a cosmetologist would allow the hair to cool before styling?

• a. when salt side bonds are being formed by changes in pH during chemical servicing

• b. when hydrogen side bonds have been broken by the heat from a curling iron

• c. when peptide bonds between amino acids are broken by a heat lamp during color processing

• d. when disulfide bonds are converted to lanthionine bonds during servicing with a flat iron