Integumentary System Flashcards
(100 cards)
1
Q
what tissues make up the integument system?
A
epithelial and connective tissue
2
Q
three major regions of integument
A
epidermis
dermis
hypodermis
3
Q
epidermis
A
outermost region
epithelial cells
4
Q
dermis
A
middle region
connective tissue
5
Q
hypodermis
A
superficial fascia/subcutaneous fat
connective tissue
6
Q
functions of integumentary system
A
protection
homeostasis
blood reservoir
sensation
metabolism
excretion
7
Q
protection
A
chemical, physical, and biological barrier
cold and heat, mechanical impact, chemical and physical damage, microorganism penetration, pressure, vibration, excessive dehydration
8
Q
homeostasis
A
control body temperature
dilation (cooling) and constriction (warming) of dermal vessels
sweat gland secretions to cool body
9
Q
blood reservoir
A
skin blood vessels store up to 5% of blood volume
10
Q
sensation
A
receptors for touch, pain, and temperature
11
Q
metabolism
A
synthesis of vitamin D
detoxification
12
Q
excretion
A
nitrogenous wastes, water and salt through sweat
13
Q
cells of epidermis
A
keratinocytes
melanocytes
dendritic cells
Merkel cells
14
Q
keratinocytes
A
produce fibrous protein keratin
main cell type
15
Q
melanocytes
A
produce brown pigment melanin
16
Q
dendritic cells
A
Langerhans cells
epidermal macrophages to help activate immune system
17
Q
Merkel cells
A
touch receptors associated with sensory nerve endings
18
Q
thick skin vs thin skin
A
thin is missing stratum lucidum layer
thinnest skin is eyelid
thickest skin is heel of foot
19
Q
5 layers of epidermis
A
stratum basale
stratum spinosum
stratum granulosum
stratum lucidum
stratum corneum
20
Q
stratum basale (basal)
A
deepest epidermal layer
rapid division
single cell layer at bottom of epidermis
give rise to keratinocytes and basale stem cells
21
Q
stratum spinosum (prickly)
A
above basale
newly differentiated keratinocytes anchored by desmosomes
lots of melanin granules from melanocytes to protect keratinocyte from UV
dendritic cells
22
Q
stratum granulosum (granular)
A
above spinosum
1-5 cell layers thick
waterproofing and toughness
keratinocytes start to accumulate much more keratin
release water resistant glycolipids
23
Q
stratum lucidum (clear)
A
above granulosum
transparent band only few layers thick
made from flattened dead keratinocytes
only visible in thick skin
24
Q
stratum corneum (horny)
A
outermost layer of keratinized cells, dead/dying cells undergoing apoptosis
makes up 75% of epidermis (20-30 cell layers thick)
25
function of stratum corneum
waterproofing
protection from abrasion and penetration
protection from biological, chemical, and physical assaults
26
contents of dermis
nerves
blood and lymph vessels
glands and follicles
27
cell types present in dermis
fibroblasts (connective tissue
macrophages
white blood cells
mast cells
28
two layers of dermis
papillary - loose areolar
reticular - dense irregular
29
papillary layer
areolar connective tissue with loose collagen and elastic fibers
dermal papillae- superior surface of finger like projections (make up fingerprints)
30
contents of dermal papillae
capillary loops for blood supple
Meissner's corpuscles for touch receptors
free nerve endings for pain receptors
immune cells
31
reticular layer
dense irregular connective tissue
collagen fibers for strength and resiliency, elastic fibers for stretch-recoil
makes 80% of thickness of dermis
32
what makes the flexure lines on hands/fingers?
when reticular layer of dermis is deeply connected to fascia
occurs at joints
33
where is tattoo ink located?
in dermis
34
complications of tattoo
granuloma- local inflammation
allergic reaction to dyes
35
composition of hypodermis
subcutaneous layer
adipose tissue and areolar connective tissue
36
functions of hypodermis
insulation
shock absorption
anchors skin to muscles loosely
37
three pigments of skin color
melanin- yellow, red, brown, black
carotene- yellow orange
hemoglobin- reddish
38
melanin
made by melanocytes and transported to keratinocytes
more sunlight --> more melanin
39
how are freckles or moles formed?
local accumulations of melanin
40
how does melanin help with cancer?
more melanin in skin, lower incidence of skin cancer
more protection from UV rays
41
carotene
yellow/orange
found in palms and soles of feet
vitamin A
42
hemoglobin
reddish
responsible for pinkish hue of pale skin
blood in capillary beds close to skin
43
why did northwest europeans lose ability to tan?
produce a defective form of mc1r necessary for protection of melanin
skin burns and peels rather than tans
44
sun poisoning/sun burn
response to UV damaging DNA causes inflammation
stimulation of DNA repair and melanin production
damaged cells undergo apoptosis -shed skin
45
vitamin D
majority made by skin with UVB photons
increases intestinal absorption of calcium, iron, magnesium, phosphate, and zinc
46
sudoriferous sweat glands
sweat glands
47
four types of sudoriferous glands
eccrine
apocrine
ceruminous
mammillary
48
eccrine sweat glands
many, found in palms, soles of feet, and forehead
coiled gland with opening at surface
release dilute solution of salts, vit C, dermicidin, and wastes
part of autonomic nervous system
49
reactions lead to location of sweat
heat at forehead
fear at palms, armpits, and arms
50
apocrine sweat glands
found in axillary and anogenital areas
duct empties into follicles
function starts at puberty and influenced by hormones
releases sweat, lipids, and proteins by exocytosis
51
ceruminous glands
modified apocrine glands in external ear canal that secrete cerumen (earwax)
52
mammary glands
specialized sweat glands that secrete milk
53
sebaceous glands
oily secretion called sebum
most active after puberty due to hormones
all over body, out growth of hair follicle
cell rupture
54
what does sebum do?
softens skin and hair
slows water loss from skin
bactericidal
55
which gland is blocked in teenagers with acne?
sebacious
56
the most important role of the eccrine sweat gland?
body temperature regulation
(also stress inducing sweat)
57
why does skin wrinkle in water?
nervous system response- vasoconstriction
better at manipulating objects
58
types of sensory receptors
thermoreceptors
mechanoreceptors
Meissner's corpuscles
Pacinian corpuscles
59
thermoreceptors
respond to temperature changes
non-encapsulated free nerve endings
60
mechanoreceptors
respond to mechanical forces like touch, pressure, and vibration
on hair follicles
61
Meissner's corpuscles
found in dermal papillae in top of dermis
discriminates light touch
62
Pacinian corpuscles
deep in dermis/subcutaneous tissue
sense applied pressure
63
functions of hair
maintain warmth
alert system
guards scalp against physical trauma, heat loss, and sunlight
guards eyes and nose against foreign particles
64
distribution of hair
all over body except
palms, soles and lips, and nipples and portions of external genitalia
65
hair
strands of dead keratinized cells (like outer layer of epidermis)
produced by hair follicles
pigment from melanocytes
66
parts of hair follicle
shaft- projects from skin
root- embedded in dermis
arrector pili- smooth muscles that pull hair erect
67
three cell layers of hair shaft
medulla
cortex
cuticle
68
hair follicle
surrounds hair shaft
deep end expands to form bulb filled with stem cells
papilla provides nutrients and growth signals (made of connective tissue and capillaries)
69
hair color
blonde-brown-black- melanin pigments from melanocytes
red- iron containing pigment pheomelanin
gray-white- gene related reduction in melanin production or age related environmental stresses
70
hair cycles
amount of time spent cycling changes depending on type of hair
growth, regression, resting phases
71
hair thinning/baldness
hair growth rates slow in 40's
alopecia- autoimmune attacks hair cells
male pattern baldness genetically determined
72
nails
scale like modification of epidermis (hard keratin)
provides protection and increased grasping ability
73
three skin injuries
blister
stretch marks
sun damage
74
blister
fluid filled pocket that forms between epidermis and dermis
75
stretch marks
striae
scars formed when dermis is torn by excessive stretching during pregnancy
76
sun damage
clumping of elastic fibers that leads to leathery skin
too much exposure to the sunlight
77
skin cancer
1 in 5 americans diagnosed
most are benign and do not metastasize
result from mutation of p53 gene
from UV exposure
78
three types of skin cancers
basal cell carcinoma
squamous cell carcinoma
melanoma
79
basal cell carcinoma
least malignant
stratum basale cells proliferate and invade the dermis and hypodermis
slow growing and rarely metastasize
cured by surgery
80
squamous cell carcinoma
arise from keratinocytes from stratum spinosum
found on scalp, ears, and lower lip
rapid growth and will metastasize if not removed
surgery or radiation therapy
81
melanoma
cancer of melanocytes
most dangerous- highly metastatic, resistant to chemotherapy
82
ABCD rule for melanoma
Asymmetry- two sides of pigmented area don’t match
Border- irregular and exhibits indentations
Color- pigmented area is black, brown, tan, sometimes red or blue
Diameter- larger than 6 mm
83
treatment for melanoma
wide surgical excision with immunotherapy
survival is poor if lesion is over 4 mm thick into skin
84
dermatofibroma
benign
epidermal layers normal
disordered collagen
85
age effects on skin
1. thinner skin as replacement slows
2. dry and itchy
3. subcutaneous fat layer diminishes, intolerance to cold
4. decreased elasticity- wrinkles
5. skin cancer risk increases- fewer melanocytes and dendritic cells
86
urticaria
inflammatory disorder
hypersensitivity to environmental exposure
cells release inflammatory cytokines
capillaries leak into dermis leading to edema
87
eczema
inflammatory disorder
dry itchy red skin
autoimmune function - cells attack skin
intracellular edema
88
psoriasis
chronic inflammation
epidermal hyperplasia in spinosum layer
elongation of papillary projections
89
microbial disorders
impetigo- by staph or strep bacteria in children
ringworm- fungal infection, tinea, on groin, feet, scalp, nails
90
diabetic dermopathy
most common disorder in diabetes
found on lower legs
hypothesis- excess glucose leads to cross linking of collagen
dermis
91
acanthosis nigricans
rough dark patches on neck
linked to obesity and insulin resistance
epidermal keratinocyte and dermal fibroblast proliferate
92
burns
heat, electricity, radiation, chemicals
risk: dehydration, electrolyte imbalance, infection
93
first degree burn
only epidermis is damaged
localized redness, swelling and pain
94
second degree burn
epidermis and upper regions of dermis are damaged
blisters - fluid filled between dermis and epidermis
95
third degree burn
entire thickness of skin is damaged
burned area is gray-white, red, or black
no edema or pain bc nerve endings burnt off
treated with skin grafts to prevent fluid loss or infection
96
rule of nines
estimates severity of burns
divide body in 11 regions, each region accounts for 9% of body surface
97
critical burn criteria
1. over 25% of body has second degree
2. over 10% of body has third degree
3. third degree burns on face, hands, or feet (respiratory passageways)
98
burn treatment
supplementary nutrients by IV to replace lost proteins and begin repair
99
sepsis
widespread bacterial infection
leading cause of death in burn victims
100
skin grafts
autografts from own skin to replace burnt skin
best method to prevent rejection
