chapter 5

Question 1

Name 3 external functions of the skin.

Answer 1

Regulating body temperature
Protection
Excretion

Question 2

Name 4 internal functions of the skin.

Answer 2

Sensation
Immunity
Blood reservoir
vitamin D synthesis

Question 3

Name the 3 general layers of the skin

Answer 3

Epidermis
Dermis
Hypodermis

Question 4

Describe the epidermis.

Answer 4

Top layer
Keratinized, stratified squamous
Avascular

Question 5

Define epidermal growth factor

Answer 5

Protein hormone that stimulates growth and repair.

Question 6

Name the 4 cells of the epidermis.

Answer 6

Keratinocytes
Melanocytes
Langerhans cells
Merkel cells

Question 7

What are the layers of the skin (most superficial to most deep).

Answer 7

s. corneum
s. lucidum
s. granulosum
s. spinosum
s. basale

Question 8

What is the function of keratinocytes?

Answer 8

Make waterproofing keratin protein.

Question 9

What is the function of melanocytes?

Answer 9

Make melanin pigment protein.

Question 10

What is the function of Langerhans cells?

Answer 10

Immune system activator

Skin dendritic cells

Migrate from bone marrow

Question 11

What is the function of Merkel cells (aka: Merkel discs)?

They are also known as:

Where are they located?

Answer 11

Touch/light pressure receptors

Located in deep part of epidermis

Mechanoreceptors and Cutaneous receptors

Question 12

Describe the s. corneum.

Answer 12

20-30 layers of flat, dead keratinized cells

cells slough off

replaced from below

Question 13

Describe the s. lucidum.

Answer 13

3-5 layers of clear cells

extra protection on palms and soles of feet.

Question 14

Describe the s. granulosum.

Answer 14

3-5 layers of cells

state of degeneration

Question 15

Describe the s. spinosum.

Answer 15

8-10 layers of cells

mostly keratinocytes connected by desmosomes

Question 16

Describe the s. basale.

Answer 16

“germinativum” layer

ONE single layer of stem cells

active mitosis forms keratinocytes and melanocytes

Question 17

Describe the dermis.

Answer 17

Below epidermis

Connective tissue w/ collagen and elastic fibers

Blood vessels (vascular)

Nerves, glands, and hair follicles

Cells have an ECM

Question 18

Name the cells found in the dermis and their functions.

Fibroblasts

Macrophages

Adipocytes

Answer 18

Fibroblasts: Make connective protein fibers

Macrophages: immune function

Adipocytes: fat cells

Question 19

What are the 2 regions of the dermis?

Answer 19

Papillary dermis

Reticular dermis

Question 20

What tissue is found in the papillary dermis?

Answer 20

Areolar connective (loose).

Question 21

What are 2 important features of the papillary dermis?

Answer 21

Dermal papillae

Meissner’s corpuscles

Question 22

Bumpy “velcro”

Ridges create fingerprints

Answer 22

Dermal papillae

Question 23

Tactile sensory receptors for touch and pressure

Answer 23

Meissner’s corpuscles

Question 24

What tissue is found in the reticular dermis?

Answer 24

Dense, irregular connective tissue

Collagen and elastic fibers

Question 25

What is an important structure found in the reticular dermis?

Answer 25

Pacinian corpuscles

Question 26

Sensory receptors for deeper pressure

Answer 26

Pacinian corpuscles

Question 27

Describe the tissue of the hypodermis.

Answer 27

Superficial fascia and adipose tissue

Question 28

What is the purpose of the hypodermis?

Answer 28

Bind reticular layer to underlying organs.

Question 29

Brown/Black pigment from tyrosine

Answer 29

Melanin

Question 30

___ is secreted by melanocytes.

Answer 30

Melanin

Question 31

What determines color: amount of pigment or cell number?

Answer 31

Amount of pigment

Question 32

What is the function of melanin?

Answer 32

To protect against UV rays/decrease UV ray absorption.

Question 33

Freckles and age spots can be attributed to ___.

Answer 33

melanin

Question 34

___ is the lack of melanin.

Answer 34

Albinism They are sensitive to UV light

Question 35

___ is a pigment found in plants.

Answer 35

Carotene

Question 36

Yellow, orange pigment.

Answer 36

Carotene

Question 37

Precursor of vitamin A.

Answer 37

Carotene

Question 38

What is the main pigment found in blood?

Answer 38

Hemoglobin (Hb)

Question 39

Hemoglobin gives a "pink" color when exposed in the ___ ___.

Answer 39

dermal capillaires

Question 40

Blue-ish complexion due to Hb being depleted of O2.

Answer 40

Cyanosis

Question 41

Yellow-ish complexion due to increased heme recycling and increased bile derivatives.

Answer 41

Jaundice

Question 42

___ are epidermal derivatives and associated structures.

Answer 42

Appendages

Question 43

Hair provides __ and decreases ___ ___.

Answer 43

protection heat loss

Question 44

Define hair.

Answer 44

Columns of dead keratinized cells

Question 45

What are the three parts of hair?

Answer 45

Shaft: above surface Root: below surface, but deep into dermis 3 layers of hair: cuticle (outer), cortex (middle), medulla (inner)

Question 46

____ surrounds root of hair.

Answer 46

Follicle

Question 47

What are the four parts of the hair follicle?

Answer 47

Bulb Papilla Arrector pili muscle Hair root plexus

Question 48

What is the function of the bulb of the hair?

Answer 48

Base of the hair Houses papilla

Question 49

Describe the tissue of the hair papilla. Is there blood supply? What happens here?

Answer 49

Areolar connective tissue Blood vessels deliver nutrients Where hair cells divide

Question 50

What is the arrector pili muscle?

Answer 50

A smooth muscle bundle that straightens the follicle Chill bumps

Question 51

What is the hair root plexus?

Answer 51

Nerve endings to cause sensation.

Question 52

What is the cause of male pattern baldness?

Answer 52

Genetics An increase in a variation of testosterone that causes hair blood vessel constriction.

Question 53

What is a treatment for male pattern baldness? How does it work?

Answer 53

Rogaine. Vasodilator of hair blood vessels.

Question 54

What are the pigments that determine hair color?

Answer 54

Eumelanin and Pheomelanin

Question 55

What pigment determines blonde/brown/black hair color?

Answer 55

Less eumelanin: blonde normal eumelanin: brown more eumelanin: black

Question 56

Red colored hair is due to ____.

Answer 56

Pheomelanin deposits sulfur into the hair. Does not protect from UV rays.

Question 57

What is the cause of gray hair?

Answer 57

Decrease of melanin

Question 58

What is the cause of white hair?

Answer 58

Air bubbles in between proteins fibers

Question 59

What are sebaceous glands?

Answer 59

oil glands connected to hair follicles

Question 60

Where are sebaceous glands located?

Answer 60

Everywhere EXCEPT palms of hands and soles of feet.

Question 61

What do sebaceous glands make?

Answer 61

Sebum made of fats, cholesterol, proteins, and inorganic salts.

Question 62

What is the function of sebum?

Answer 62

Moisturize hair Decrease skin water loss Decreasing bacterial growth

Question 63

What are the two types of sudoriferous glands?

Answer 63

Eccrine Apocrine

Question 64

What are the general functions of the sudoriferous glands?

Answer 64

Body temperature regulation Secondary waste elemination/removal

Question 65

Found throughout the skin (a lot on palms and soles) Directly open to epidermis

Answer 65

Eccrine sweat glands