Ch 6-Integumentary System (Exam 2)

Question 1

What is melanin

Answer 1

Natural substance that gives color to skin, hair, eyes

Question 2

What does subcutaneous mean

Answer 2

Under the skin

Question 3

What is the largest organ in the body?

Answer 3

Skin- 15-16% of body weight

Question 4

What is the top layer of the skin?

Answer 4

Epidermis

Question 5

What is the epidermis and dermis separated by?

Answer 5

Basement membrane

Question 6

What is the epidermis nourished by? (Since it is avascular)

Answer 6

Diffusion from capillaries of the papillary layer of the dermis

Question 7

What is the epidermis composed of

Answer 7

Cells arranged into stratified layers

Question 8

What are the cells of the epidermis?

Answer 8

-stem cells
-keratinocytes
-melanocytes
-dendritic cells

Question 9

What are stem cells

Answer 9

-undifferentiated cells that give rise to keratinocytes
-in the deepest layer of the epidermis

Question 10

What is the deepest layer of the epidermis?

Answer 10

Stratum basale

Question 11

What are keratinocytes?

Answer 11

Cells of the epidermis that produce keratin (great majority of epidermal cells)

Question 12

What are melanocytes?

Answer 12

-occur only in the stratum basale
-synthesize pigment melanin that shields DNA from ultraviolet radiation

Question 13

What are dendritic cells?

Answer 13

Macrophages originating in bone marrow that guard against pathogens

Question 14

What is the only layer of the epidermis to undergo cell division?

Answer 14

Stratum basale

Question 15

What are the layers of the epidermis?
(BSGLC)

Answer 15

-Stratum basale
-stratum spinosum
-stratum granulosum (granular layer)
-stratum lucidum (clear layer)
-stratum corneum (horny layer)

Question 16

Stratum spinosum

Answer 16

made up of multiple layers of cells that are held together by desmosomes

Question 17

Stratum granulosum (granular layer)

Answer 17

-contains keratohyalin
-contains lysosomal enzymes
-contains granules
-nucleus and other organelles degenerate and cells die

Question 18

Stratum lucidum (clear layer)

Answer 18

-thin, clear zone. Found only in palms and soles
-dead cells filled with keratin precursor called eleidin

Question 19

Stratum corneum

Answer 19

-most superficial and consists of cornified cells
-outermost layer of the skin

Question 20

Layers of the epidermis in order (bottom to top)

Answer 20

1.Stratum basale (deepest layer)
2. Stratum spinosum
3. Stratum granulosum
4. Stratum lucidum
5. Stratum corneum (outermost layer of skin)

Question 21

How long does it take for epidermal cells to form in the stratum basale and migrate to the skin surface?

Answer 21

30-40 days

Question 22

What percent of cells in the stratum basale enter mitosis daily?

Answer 22

10%-12%

Question 23

Does the dermis continually shed and regenerate itself?

Answer 23

No

Question 24

Which layer plays a critical role in temperature regulation?

Answer 24

Dermis

Question 25

Dermis (true skin) qualities

Answer 25

-storage site for water and electrolytes -sensory receptors for pain, itch, tickle, pressure, touch, and temperature

Question 26

What is inside of the dermis?

Answer 26

Hair follicles, sweat and sebaceous glands, blood vessels, and muscle fibers

Question 27

What are the layers of the dermis?

Answer 27

-papillary layer -reticular layer

Question 28

Papillary layer of the dermis

Answer 28

-composed of dermal papillae that project into the epidermis -forms unique pattern that gives individual fingerprints

Question 29

Reticular layer of the dermis

Answer 29

-contains connective tissue that makes the skin tough yet stretchable -deeper layer of dermis, thicker and less cellular

Question 30

Decrease blood flow to skin leads to what

Answer 30

Pale

Question 31

Increased blood flow to skin leads to what

Answer 31

Flush (erythema)

Question 32

Albinism

Answer 32

Hair is white, skin is pale, irises of eyes are pink. Caused by lack of melanin production

Question 33

Bronzing

Answer 33

Skin appears golden brown, copper, or bronze in color. Caused by Addison disease

Question 34

Erythema

Answer 34

Skin appears abnormally red. Caused by increased blood flow

Question 35

Hematoma

Answer 35

A bruise is observable through the skin

Question 36

Jaundice

Answer 36

Skin and whites of the eyes appear yellow. Caused by elevated levels of bilirubin in the blood

Question 37

Pallor

Answer 37

Skin appears ashen, pale due to decreased blood flow to the skin

Question 38

What are the functions of the skin?

Answer 38

-protection -sensation -excretion -vitamin D synthesis -immune function -homeostasis of body temperature

Question 39

Hyperthermia

Answer 39

Abnormally high body temperature. Sweating and vasodilation

Question 40

Hypothermia

Answer 40

Abnormally low body temperature. Shivering and vasoconstriction

Question 41

Is the hypodermis part of the skin?

Answer 41

No

Question 42

Types of cells in the hypodermis

Answer 42

-fibroblasts -adipose cells -macrophages

Question 43

What does the Hypodermis consist of

Answer 43

Consists of loose connective tissue with collagen and elastic fibers

Question 44

Hypodermis and fat

Answer 44

Contains about half of the body’s fat. Functions as: energy source, insulation, padding

Question 45

Where on the body is hair located?

Answer 45

Over the entire body except palms of hands and soles of feet and a few other small areas

Question 46

What causes hair color?

Answer 46

Varying amounts and types of melanin

Question 47

Arrector pili

Answer 47

Smooth muscle. Muscle contraction causes hair to “stand on end”

Question 48

Sebaceous glands and function

Answer 48

Groups of specialized epithelial cells. Secretes sebum. Keeps hair soft, pliable, and waterproof

Question 49

Eccrine glands and function

Answer 49

Abundant sweat glands with odorless secretion. Used to lower body temperature and eliminate wastes (Small)

Question 50

Apocrine sweat glands and function

Answer 50

Sweat glands with secretions that develop odors. Wets skin during pain, fear, emotional upset, and sexual arousal

Question 51

Ceruminous glands

Answer 51

Secrete earwax

Question 52

Mammary glands

Answer 52

Secrete milk

Question 53

What are the most numerous sweat glands?

Answer 53

Eccrine glands

Question 54

When do apocrine glands begin to function?

Answer 54

At puberty

Question 55

Where are apocrine glands found?

Answer 55

Armpit, areola of breast, and around anus (large)

Question 56

What is the function of cerumen?

Answer 56

Protect area from dehydration; excess secretions can cause blockage of ear canal and loss of hearing