Chapter 5: Integumentary System Flashcards
1
Q
integument
A
skin, hair, nails, sweat glands, sebaceous glands
2
Q
functions of integumentary system (7)
A
- protection: abrasion, chemicals, water loss
- temp regulation
- sense organ (pain, hot)
- create/store vitamin D
- shields UV rays
- diagnostic organ (excessive itching is diabetes)
- sexual attraction organ (phermones)
3
Q
What are the 2 tissue layers of skin?
A
dermis
epidermis
4
Q
epidermis
A
- epithelial surface layer (5 layers)
- stratified keratinized squamous
5
Q
dermis
A
- deeper connective tissue
- binds epodermis to hypodermis
6
Q
Hypodermis (subcutaneous layer)
A
- not skin
- loose CT (mostly adipose)
- attaches dermis to deeper tissues
7
Q
4 cell types in epidermis
A
- keratinocytes
- melanocytes
- langerhans cells
- merkel cells
8
Q
keratinocytes
A
produce keratin
9
Q
melanocytes
A
produce melanin
10
Q
langerhans cells
A
- part of immune system
- derived frm bone marrow
- show forein substances to lymphocytes
11
Q
merkel cells
A
ends of sensory neurons
12
Q
How many layers are in the epidermis?
A
- varied (4 or 5)
- depends on degree of friction + mechanical pressure applied
- thick skin-non hairy parts (soles of feet, palms)
- thin skin everywhere else
13
Q
what are the layers of the epidermis (deep–>superficial)?
A
- stratum basale (germanitivum)
- stratum spinosum
- atratum granulosum
- stratem lucidum
- stratum corneum
14
Q
Stratum basale
A
- cells:
- keratinocytes: rest on basal lamina of basement mem.
- melanocytes: use enzyme (tyrosinase) to produce melanin
- merkel cells: numerous in stratum basale of fingertips (rapid mitosis)
15
Q
how do melanocytes produce and distribute melanin? What does melanin prevent?
A
- melanin granules accumulate in melanocyte and exit by pinching off
- they’re distributed through epidermis and surround nucleus
- protects DNA from genetic mutation
16
Q
stratum spinosum
A
- cells:
- keratinocytes: 8-10 layers, cuboidal and held togeter by desmosomes, accumulate keratohyalin (protein)
- langerhans: immunologically active, dont separate in areas of friction, produce karatohyalin, provides flex + strength
17
Q
stratum granulosum
A
cells:
- keratinocytes: 3-5 layers of dying with shrunken nucleus
- lamellar granules: secrete water repellent lipid sealant in cytoplasm
- keratohyalin granules are present in cytoplasm (condense and reffered to as lamelar granules for sealant)
18
Q
stratum lucidum
A
cells:
- keratinocytes: flattened, dead (transparent)
- found in thick skin
- keratohyalin forms eledin that fills cells
19
Q
stratum corneum
A
- cells:
- keratinocytes- flattened, dead, filled with keratin (formed from eledin)
- horny cells: dead karatinocytes that have dispersed all of their keratin at the upper surfaceof stratum corneum
- keratinization
20
Q
how does keratinization of the stratum corneum occur?
A
replacement of cell contents with the protein keratin as the cells migrate to the skin surface over a 2-4 week period
21
Q
callus
A
abnormal thinckening of stratum corneum
22
Q
dermis
what is it made of?
A
- made of dense regular CT that has 2 regions
- highly vascular
- supports epidermis
23
Q
what are the 2 regions of the dermis?
A
- papillary region
- reticular region
24
Q
papillary layer
A
- areolar CT
- fine elastic fibers
- dermal papillae
- nerve endings for sensations
- pushes up into epidermis (fibrous extension) to strengthen dermal epidermal junction
25
what are the types of nerve endings?
* meissners corpuscles
* ruffini receptors
26
function of arrector pilli muscle
no function in humans, protective in animals
27
reticular layer
* dense irregular CT
* bundles of collagen + elastic fibers
* spaces btwn fibers contain adipose cells, hair follicles, sebaceous glands, sudorifferous glands
28
sebaceous glands vs sudoriferous glands
sebaceous: secrete sebum into shaft
sudorifferous: secrete sweat through ducts
29
tatooing
permanent coloration of skin in which foreing pigment is injected into the dermis
30
epidermal ridges
increases friction for grasping and provides fingerprints and footprints
31
3 pigments in the dermis
1. melanin
2. carotene
3. hemoglobin
32
albanism
* inherited inability to produce melanin
* have melanocytes without melanin production
* symptoms: pink eyes, white skin & hair, high sunburn & skin cancer risk
33
vitiligo
* complete or partial loss of melanocytes from patches f skin
* results in irregular white spots
* immunological disease or from thyroid disfunction or head trauma
34
accessory structures of the skin
hair, glands, nails
35
hairs or pilli
present on most skin surfaces except palms, palmar surfaces of fingers, soles and plantar surface of toes
36
what does hair consist of?
* shaft above the surface
* root that penetrates the dermis and subcutaneous layer, cuticle, hair follicle & arrecto pilli muscle
37
what does arrector pilli muscle do? how?
* connected to hair follicle
* rotates hair perpendicular through skin
* pushes skin and causes goose bumps
* smooth muscle
38
cuticle
description
function
* 1 cell thick
* heavy
* keratinized
* loo like clear interlocking shingles
* assist in anchoring hair in place
39
hair follicle
contains actively mitotic cells that will produce new hair or repair damaged hair
40
what is hair color due to?
amount and type of melanin
41
graying of hair occurs because?
progressive decline in enzyme tyrosinase
42
why is tyrosinase used?
melanocytes use tyrosinase to convert melanin to eledin
43
sebaceous glands
* connected to hair follicles and produce sebum
* keeps skin and hair soft/waterproof and inhibits bacterial growth
* ducts empty into neck of hair folliclle everywhere except lips, genitalia, nipples
44
acne
results when sebaceous glands become plugged with dirt or white blood cells
45
sudoriferous (sweat) glands
divided into eccrine and apocrine type to rpoduce sweat
46
persperation consists of
* water
* NaCl
* protein
* urea
* polysaccharides
47
perspire in response to what?
parasympathetic nervous system
48
eccrine sweat glands
have ducts that terminate at pores at the surface of the epidermis
49
apocrine sweat glands
location
description
* located in axilla, pubis, areola
* ducts open into hair follicles
* secretion is viscous causing odor
* simulated by sex hormones and emotional stress
* controlled by sympathetic nervous system
50
51
nails
hard plates of keratinized epidermal cells over the posterior surfaces of the terminal portions of fingers/toes
52
nails help to
grasp, mmanipulate small objects and provide protection against trauma to the ends of digits
53
nail conditions
cyanosis, spooning
54
cyanosis symptoms
* blue to purple discoloration of skin
* whites of eyes
* mucus mmebranes due to a lack of hemoglobin bound oxygen
55
emphisima COPD
nails take on shape of spoon
56
thin skin
* covers all parts of the body except palms and palmar surfaces of digits/toes
* lacks stratum lucidum and epidural ridges
57
thick skin
* covers palms, palmar surfaces of digits/soles
* contains stratum lucidum and thick epidural ridges
* lacks hair follicles, arrector pilli muscles, sebaceous glands
* contains more sweat glands than skin
58
when an injury to tissues extends deep into the epidermis
the repair process results in scar tissues formation or fibrosis
59
inflammatory phase
* blood clot unites the wound edges
* epithelial cells migrate across the wound
* vasodilation and increased permeability of blood vessels deliver phagocytes & fibroblasts
60
migratory phase
* epithelial cells beneath the scab bridge the wound
* fibroblasts begin scar tissue
* damaged blood vessels begin to grow
* tissue filling wound is granulation tissue
61
proliferation phase
events of the migratory phase intensify
62
maturation phase
* scab sloughs off
* epidermis is restored to normal thickness
* collagen fibers become more organized
* fibroblasts begin to disappear
* blood vessels are resored to normal
63
decubitus ulcer (pressure sore)
cause
constant deficiency of blood to the tissues over a bony projection that has been subjected to prolonged pressure against an object such as a bed, cast, splint
64
where do you get pressure sores?
most susceptible tissues: sacrum, ischia (pelvis), femurs, bumps on ankle (malleoli)
