U3: Skin and Body Membranes

Question 1

Cutaneous Membrane (what is it, function 8)

Answer 1

Skin technical term

Provides a protective barrier.
Insulates and cushions.
Prevents loss of moisture.
Reduces harmful effects of UV radiation.
Excretes urea, salts, and water
Synthesizes vitamin D
Manufactures protein needed for immunity
Sensors alert us to external environment

Question 2

Skin Derivatives

Answer 2

Sweat glands, oil glands, hair, and nails

Question 3

Outer layer of skin (what is it, made of, has, and blood vessles?)

Answer 3

epidermis

made of stratified squamous epithelium
keratinized (hardened by keratin - fibers protein produced by keratinocytes)
avascular (without blood vessels)

Question 4

Middle layer of skin (what is it, made of, blood vessels?)

Answer 4

dermis

Dense connective tissue
vasular

Question 5

Bottom layer of skin

Answer 5

hypodermis or subcutaneous

Anchors skin to underlying organs
Composed mostly of adipose tissue
Serves as a shock absorber
Insulates deeper tissue from extreme temperature changes

Question 6

Stratum Corneum (CLGSB)

Answer 6

shingle like dead cells filled with keratin
cells held together with proteins
Important barrier that keeps molecules from passing through skin
3/4 of epidermal thickness

Question 7

Straum Lucidum (CLGSB)

Answer 7

translucent cells that have accumulating keratin
secretes a water-repellant glycoprotein
occurs only in the thick skin where it helps reduce friction

Question 8

Stratum Granulosum (CLGSB)

Answer 8

Keratin proteins and water-proofing lipids are produced and organized

Question 9

Stratum Spinosum (CLGSB)

Answer 9

cells change from columnar to polygonal shapes and starts to synthesize keratin

Question 10

Stratum Basale (CLGSB)

Answer 10

deepest layer
cells undergo mitosis
receive the most nourishment via diffusion from the dermis

Question 11

Melanin

Answer 11

A yellow, to brown, to black pigment produced by cells called melanocytes

Melanocytes found mostly in the Stratum Basale

Amount depends on genetics and exposure to sunlight

Question 12

What does sunlight do to melanin?

Answer 12

sunlight exposure stimulates pigment production

too much can damage skin, depress the immune system, and alter your skin

Question 13

Dermis

Answer 13

made of dense connective tissue

Question 14

What do the collagen fibers provide?

Answer 14

toughness and attract and bind water to keep the skin hydrated

Question 15

What do the elastic fibers provide

Answer 15

responsible for elasticity when we are young

Question 16

What is the upper layer of the dermis

Answer 16

papillary layer

Question 17

what does the upper layer of the dermis contain

Answer 17

finger-like projections called dermal papillae
pain receptors called free nerve endings
touch receptors called Meissner’s corpuscles

Question 18

What is the dermis responsible for

Answer 18

fingerprints

Question 19

What is the deepest layer of the dermis

Answer 19

reticular layer

Question 20

What does the deepest layer of the dermis contain?

Answer 20

blood vessels
sweat and oil glands
nerve receptors
deep pain receptors called pacinian corouscles
phagocytes

Question 21

phagocytes

Answer 21

a type of cell within the body capable of engulfing and absorbing bacteria and other small cells and particles.

Question 22

What are the normal skin color determinants

Answer 22

hemoglobin
melanin
carotene

Question 23

hemoglobin

Answer 23

red coloring from blood cells in the dermis capillaries

oxygen content determines the extent of red coloring
- well oxygenated -> pink tones
- less oxygenated -> blue tones

Question 24

Carotene

Answer 24

orange to yellow pigment from some vegetables

Question 25

Erythma

Answer 25

Redness
fever, embarrassment, hypertension, allergy

Question 26

Blanching

Answer 26

Pallor (paling of skin)

fever, anger, anemia, low blood pressure

Question 27

Jaundice

Answer 27

Yellow cast caused
liver disorder

Question 28

Bruises

Answer 28

hematomas
blood escaped circulation and clotted in tissue spaces

Question 29

Keratin

Answer 29

protein that helps form hair, nails and your skin’s outer layer (epidermis). It helps support your skin, heal wounds and keep your nails and hair healthy

Question 30

What do the appendages of the skin do?

Answer 30

all arise from the epidermis and all play a unique roll in maintaining homeostasis