Skin

Question 1

types of epithelial membranes

Answer 1

cutaneous, mucous, serous

Question 2

connective tissue membrane

Answer 2

synovial

Question 3

cutaneous membrane

Answer 3

-skin
-superficial epidermis: stratified squamous epithelium
-underlying dermis: dense connective tissue
-exposed to air: dry membrane

Question 4

Mucous membrane

Answer 4

-lines body cavities open to exterior
-respiratory, digestive, urinary, reproductive
-rests on loose connective tissue called lamina propitia with various types of epithelium attached
-wet/moist: continuously bathed in secretions
-adapted for absorption, secretion
-digestive/resp secrete mucous
-urinary bathed in urine

Question 5

Serous membranes

Answer 5

-line body cavities enclosed to exterior
-simple squamous epithelium- rests on areolar connective tissue
-occur in pairs:
-Parietal: outer wall; lines body cavity
-Visceral: inner wall; lines organ

Question 6

Serous membrane layers

Answer 6

-layers separared by serous fluid
-thin, clear fluid secreted by both membranes
- allowes organs to slide across cavity walls without friction ex: heart and stomach
-specific names dependant on location
1.peritoneum-lining of abdominal cavity
2. pleura-lungs
3. pericardium-heart

Question 7

synovial membrane

Answer 7

• line capsules surrounding joints, bursa (sacs), tendons
• areolar connective tissue- no epithelial calls
• provide smooth surface and secretes lubricating fluid: synovial fluid

Question 8

Keratin

Answer 8

-fibrous protein
- makes epidermis tough protective layer
-toughens cells
-impermeable
-waterproofs

Question 9

integumentary system functions

Answer 9

• protects
  -insulates and cushions deeper body organs
  -damage:
  -Mechanical: bumps and cuts
  -Chemical: acids and bases
  - Bacterial
  -Thermal: heat and cold
  
  • from UV radiation
  • from drying out
    -regulates heat loss
    -excretes salts, water, urea via sweat
• manufactures proteins for immunity
• synthesizes vitamin D
• houses cutaneous sensory receptorrs

Question 10

Epidermis

Answer 10

-outer layer
- stratified squamous epithelium
-cells here produce and contain keratin
-keritinizing- becoming hard and tough
-avascular: no blood supply of it’s own)
- keritinocytes- produce keritin and a fiberous protein which makes the epidermis a tough protective layer

Question 11

epidermis contains 5 zones (strata)

Answer 11

-closest to dermis (stratum Basale) nourished via diffusion of nutrients from dermis. undergo constant cell division
- daughter cells push away from dermis to move superficial strata layers; became flatter, more keritinized
- second most superficial (stratum Lucidium): found in hairless, extra thick body parts ( hands, soles of feet)
- outermost (Stratum corneum): 20-30 cell layers thick; 3/4 of epidermal thickness; shingle like, dead cells reminants; completely keritinized

Question 12

melanin

Answer 12

-pigment produced and found in stratum basale
- ranges from yellow to brown to black
- sunlight stimulates production=tanning
- melanin is produced as protection for DNA

Question 13

Dermis (“hide”)

Answer 13

• underlies epidermis, firmly connected
• dense connective tissue
• thick on palms of hands and soles of feet, thin on eyelids
• BV maintain body temp.
  -Contains collagen (toughness, hydration) and elastic fibers ( decrease w/age)
  -rich nerve supply

Question 14

papillary layer

Answer 14

upper region
-uneven, contain papillae (fingerlike projections)
- contains capillary loops ( furnish nutrients to epidermis)
- house pain and touch receptors
- genetically ditermined rigid patterns on hands and feet increase friction, enhance gripping (fingerprints)

Question 15

reticular layer

Answer 15

deepest skin layer
-contains blood vessels, sweat and oil glands, deep pressure receptors
- immune system activity occurs here.

Question 16

hypodermis

Answer 16

deep to dermis
- adipose connective tissue
- not considered part of skin
- anchors skin to underlying organs
- shock absorber
- insulates from extreme temp changes

Question 18

carotene

Answer 18

orange-yellow, found in carrots/ other orange/yellow/ leafy green vegetables; in stratum and hypodermis

Question 19

exocine cutaneous glands

Answer 19

release secretions to skin surface via ducts
- formed in stratum, push in to deeper skin regions, reside in dermis

Question 20

sebacious cutaneous glands

Answer 20

oil glands
- found everywhere besides palms and soles
- most ducts empty into hair follicles, some direct to skin

Question 21

sebum

Answer 21

mixture of only substances and fragmented cells
- lubricant keeps skin soft and moist, prevents brittle hair
- contains chemicals that kill bacteria
-active during adolecence

Question 22

suderiferous eccrine

Answer 22

more, numerous,found everywhere
-produces sweat (water salts, vatamin C,tracemetabolic watstes, lactic acid)
- sweat reches skin via funnel shaped pore ducts
- important for body tempregulation

Question 23

suderiferous apocrine

Answer 23

-axillary and genital body areas
-larger; ducts empty into hair follicles
-contain fats and proteins used as source of nutrients for bacteria growth (cause odor); milky yellowish color
- begin to function during puberty
- activated by nerves during pain and stress