Chapter 6

Question 1

The integumentary system

Answer 1

separates and protects us from the external environment.

Question 2

The epidermis is stratified squamous epithelium divided into five strata,

Answer 2

from deep to superficial: stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum.

Question 3

Keratinization

Answer 3

is the transformation of the living cells of the stratum basale into the dead squamous cells of the stratum corneum.

Question 4

Soft vs hard keratin

Answer 4

Soft keratin is present in skin and the inside of hairs, whereas hard keratin occurs in nails and the outside of hairs.

Question 5

Thin vs thick skin

Answer 5

Thick skin has all five epithelial strata.

Thin skin contains fewer cell layers per stratum, and the stratum lucidum is usually absent. Hair is found only in thin skin.

Question 6

Melanocytes

Answer 6

produce melanin inside melanosomes and then transfer the melanin to keratinocytes.

Question 7

Carotene

Answer 7

an ingested plant pigment, can cause the skin to appear yellowish.

Question 8

cyanosis.

Answer 8

Decreased oxygen content in the blood results in a bluish color,

Question 9

The dermis is connective tissue divided into two layers.

Answer 9

Papillary and reticular layer

Question 10

the subcutaneous tissue

Answer 10

Located beneath the dermis, is loose connective tissue that contains collagen and elastic fibers.

Question 11

A hair has three parts

Answer 11

shaft, root, and hair bulb

Question 12

Lanugo

Answer 12

fetal hair) is replaced near the time of birth

Question 13

terminal hairs

Answer 13

(scalp, eyelids, and eyebrows)

Question 14

vellus hairs

Answer 14

At puberty, vellus hairs can be replaced with terminal hairs.

Question 15

Contraction of the arrector pili muscles

Answer 15

which are smooth muscles, causes hair to “stand on end” and produces “goose bumps.”

Question 16

Sebaceous glands

Answer 16

produce sebum, which oils the hair and the surface of the skin.

Question 17

Eccrine sweat glands .

Answer 17

produce sweat, which cools the body

Question 18

Apocrine sweat glands

Answer 18

produce an organic secretion that can be broken down by bacteria to cause body odor.

Question 19

ceruminous glands

Answer 19

, which make cerumen (earwax)

Question 20

Nail root vs. body

Answer 20

The nail root is covered by skin, and the nail body is the visible part of the nail.

Question 21

The lunula.

Answer 21

is the part of the nail matrix visible through the nail body

Question 22

The nail

Answer 22

is stratum corneum containing hard keratin.

Question 23

cholecalciferol

Answer 23

Produced by ultra violet light, which is modified in the liver and then in the kidneys to form active vitamin D.

Question 24

Calcitriol

Answer 24

Active vitamin D, l, increases blood calcium levels by promoting calcium uptake from the small intestine.