Chapter 5 pt. 2

Question 1

What 3 pigments contribute to skin color?

Answer 1

• Melanin
• Carotene
• Hemoglobin

Question 2

What is Melanin?

Answer 2

only pigment made in skin; made by melanocytes but packaged by keratinocytes

Question 3

What is Carotene?

Answer 3

yellow to orange pigment in the skin; carrots can produce carotene

Question 4

What is Hemoglobin?

Answer 4

a pinkish hue of fair skin due to lower levels of melanin

Question 5

Cyanosis

Answer 5

blue skin color due to low oxygenation of hemoglobin

Question 6

What does hair consist of?

Answer 6

dead keratinized cells (contains hard keratin, which is tougher and more durable)

Question 7

Three parts of hair shaft:

Answer 7

medulla (central core), cortex (layers surrounding medulla), and cuticle (outer layers)

Question 8

What are hair pigments made of?

Answer 8

melanocytes in hair follicles (red hair has additional pheomelanin pigment)

Question 9

hair matrix

Answer 9

actively dividing the area of the bulb that produces hair cells
- as new cells are made, older cells are pushed upward

Question 10

Arrector Pili

Answer 10

small band of smooth muscle attached to follicle
- responsible for “goose bumps”

Question 11

hair papilla

Answer 11

Dermal tissue containing a knot of capillaries that supplies nutrients to growing hair

Question 12

Hair follicle receptor

Answer 12

sensory nerve endings that wrap-around bulb

Question 13

types of hair

Answer 13

vellus (pale, fine) and terminal (coarse)

Question 14

Homeostatic Imbalance (hair)

Answer 14

• hirsutism: excessive hairiness due to abnormally large amounts of androgens
• alopecia: hair thinning after 40y/o
• true baldness: genetically determined and sex-influenced
• baldness in males caused by follicular response to DHT (dihydrotestosterone)

Question 15

What do nails consist of?

Answer 15

hard keratin, free edge, nail plate, and root

Question 16

nail matrix

Answer 16

thickened portion of bed responsible for nail growth

Question 17

nail bed

Answer 17

epidermis underneath keratinized nail plate

Question 18

nail fold

Answer 18

skin folds that overlap border of nail

Question 19

What is the eponychium of the nail?

Answer 19

nail fold that projects onto surface of nail body; also referred to as the cuticle

Question 20

What is the thick, white nail matrix called?

Answer 20

Lunule

Question 21

What are the two types of sweat glands?

Answer 21

• Eccrine (or merocrine)
• Apocrine

Question 22

Eccrine Sweat Glands

Answer 22

• Most numerous type
• Abundant on palms, soles, and forehead
• Ducts connect to pores

Question 23

Apocrine Sweat Glands

Answer 23

• Confined to axillary and anogenital areas
• Secrete viscous milky or yellowish sweat that contains fatty substances and proteins

Question 24

Two modified apocrine glands?

Answer 24

Ceruminous (earwax) and Mammary (lactation) glands

Question 25

Sebaceous (Oil) Glands

Answer 25

Most develop from hair follicles and secrete into hair follicles; Widely distributed, except for thick skin of palms and soles

Question 26

What do sebaceous glands secrete?

Answer 26

sebum: oily holocrine secretion, bacterial killing properties, softens hair and skin

Question 27

the functions of the skin:

Answer 27

protection, body temp regulation, cutaneous sensations, metabolic functions, blood reservoir, excretion of wastes

Question 28

Protection constitutes what three barriers?

Answer 28

chemical, physical, and biological

Question 29

cutaneous sensory receptors are a part of what body system?

Answer 29

nervous system

Question 30

insensible perspiration vs sensible perspiration

Answer 30

IP: under normal, resting body temperature, sweat glands produce about 500 ml/day of unnoticeable sweat SP: if body temperature rises, dilation of dermal vessels can increase sweat gland activity to produce 12 L (3 gallons) of noticeable sweat

Question 31

Pallor

Answer 31

blanching or pale skin caused by anemia, low blood pressure, fear, or anger

Question 32

Erythema

Answer 32

redness of the skin due to fever, hypertension, inflammation, or allergy

Question 33

Jaundice

Answer 33

yellow cast due to liver disorders

Question 34

Bruises

Answer 34

Also referred to as ecchymoses or hematomas, are a result of clotted blood beneath skin