Integumentary System - AnaPhy Lecture Flashcards
1
Q
- covers the entire body
- has a surface area of 1.2 to 2.2 square meters
- weighs 4–5 kg
- about 7% of total body weight in the average adult
- thickness - 1.5 to 4.0 millimeters
A
Skin
2
Q
skin has a surface area of
A
1.2 to 2.2 square meters
3
Q
skin weighs
A
4-5 kg
4
Q
skin is about what percentage of total body weight in the average adult
A
7%
5
Q
skin thickness is
A
1.5 to 4.0 millimeters
6
Q
the skin protects deeper tissues from
A
- Mechanical damage
- Chemical damage
- Bacterial damage
- Thermal damage
- Ultraviolet radiation
- Desiccation
7
Q
Functions of the skin
A
- Protects deeper tissues from:
- Mechanical damage
- Chemical damage
- Bacterial damage
- Thermal damage
- Ultraviolet radiation
- Desiccation - Aids in heat regulation
- Aids in excretion of urea and uric acid
- Synthesizes vitamin D
8
Q
Cells of the Epidermis
A
- Keratinocytes
- Melanocytes
- Dendritic cells
- Tactile cells
8
Q
produce keratin, the fibrous protein that helps give the epidermis its protective properties
A
Keratinocytes
9
Q
the fibrous protein that helps give the epidermis its protective properties
A
keratin
10
Q
most epidermal cells are
A
Keratinocytes
11
Q
keratinocytes arise from
A
stratum basale
12
Q
undergo almost continuous mitosis in response to prompting by epidermal growth factor, a peptide produced by various cells throughout the body
A
Keratinocytes
13
Q
Millions of dead keratinocytes rub off every day, giving us a
totally new epidermis every
A
25 to 45 days
14
Q
cell production and keratin formation is accelerated in body areas regularly subjected to _____________, such as the hands and feet
A
friction
15
Q
cell production and keratin formation is accelerated in body areas regularly subjected to friction, such as the
A
hands and feet
16
Q
the spidershaped epithelial cells that synthesize the pigment melanin
A
Melanocytes
17
Q
melanocytes accumulates in membrane-bound granules called
A
melanosomes
18
Q
are transferred to nearby keratinocytes
A
melanin
19
Q
accumulate on the superficial, or “sunny,” side of the keratinocyte nucleus, forming a pigment shield that protects the nucleus from the damaging effects of ultraviolet (UV) radiation in sunlight
A
melanin granules
20
Q
star-shaped cells that arise from bone marrow and migrate to the epidermis
A
dendritic cells
21
Q
dendritic cells are also called
A
Langerhans cells
22
Q
ingest foreign substances and are key activators of our immune system
A
dendritic cells
23
Q
star-shaped dendritic cells arise from
A
bone marrow
24
present at the epidermal-dermal junction
Tactile (Merkel) cells
25
shaped like a spiky hemisphere
Tactile (Merkel) cells
26
each tactile cell is intimately associated with a
disc-like sensory nerve ending
27
functions as a sensory receptor for touch.
Tactile (Merkel) disc
28
Two distinct layers of the skin
Epidermis and dermis
29
made up of stratified squamous epithelium, hardened by keratin
Epidermis
30
making up the bulk of the skin, is a tough, leathery layer composed mostly of fibrous connective tissue, vascularized
Dermis
31
The subcutaneous tissue just deep to the skin is known as the
hypodermis
32
Layers of the Epidermis
1. Stratum basale
2. Stratum spinosum
3. Stratum granulosum
4. Stratum lucidum
5. Stratum corneum
33
deepest epidermal layer
Stratum basale
34
consists of a single row of stem cells—a continually renewing cell population
Stratum basale
35
a continually renewing cell population
stem cells
36
Each time one of these basal cells divides, one daughter cell is pushed into the cell layer just above to begin its specialization into a
mature keratinocyte
37
10-25% of cells in the stratum basale are
melanocytes
38
contain a weblike system of intermediate filaments, mainly
tension-resisting bundles of pre-keratin filaments, which span their cytosol to attach to desmosomes
Stratum spinosum
39
Scattered among the keratinocytes (in stratum spinosum) are
melanin granules and dendritic cells
40
consists of four to six cell layers in which keratinocyte appearance changes drastically
Stratum granulosum
41
- process of keratinization begins
- Nutrient-poor layer
Stratum granulosum
42
Cells flatten, their nuclei and organelles begin to disintegrate
Stratum granulosum
43
stratum granulosum accumulates two types of granules:
keratohyaline granules and lamellar granules
44
help to form keratin in the upper layers (darkly stained)
keratohyaline granules
45
contain a waterresistant glycolipid that prevents water loss
across the epidermis
lamellar granules
46
- visible only in thick skin
- consists of two or three rows of clear, flat, dead keratinocytes with indistinct boundaries
Stratum lucidum
47
strong, flexible connective tissue
Dermis
48
Cells types in Dermis
fibroblasts, macrophages, and occasional mast cells and white blood cells
49
Dermis has a rich supply of
supply of nerve fibers, blood vessels, and lymphatic vessels
50
has a rich supply of nerve fibers, blood vessels, and
lymphatic vessels
Dermis
51
two layers of the dermis
papillary layer and reticular layer
52
peglike projections
Dermal papillae
53
contain capillary loops
Papillary layer
54
house free nerve endings (pain receptors) and touch receptors called tactile or Meissner corpuscles
Papillary layer
55
the papillary layer house free nerve endings (pain receptors) and touch receptors called
tactile or Meissner corpuscles
56
Dermal papillae lie atop larger mounds called
dermal ridges
57
Dermal papillae lie atop larger mounds called dermal ridges,
which in turn cause the overlying epidermis to form
epidermal ridges
58
These _______________ cause the overlying epidermis to fold into ridges on the fingers that are called fingerprints, which are unique to each individual.
dermal papillae
59
about 80% of the thickness of the dermis
reticular layer
60
coarse, irregularly arranged, dense fibrous connective tissue
reticular layer
61
orientation of collagen fibers in the dermis, and are
generally parallel to the orientation of the underlying
muscle fibers
Cleavage (tension) lines
62
are important to surgeons because when an incision is made parallel to these lines, the skin gapes less and heals
more readily.
Cleavage lines
63
dermal folds that occur at or near joints, where the dermis is tightly secured to deeper structures
Flexure line
64
Three pigments contribute to skin color:
Melanin, Carotene, Hemoglobin
65
Yellow, brown or black pigments; produced by melanocytes
melanin
66
pigments produced by melanin
Yellow, brown or black pigments;
67
Melanin production depends upon
genetic and exposure to sunlight
68
Orange-yellow pigment from some vegetables
carotene
69
Red coloring from blood cells in dermis capillaries
Hemoglobin
70
determines the extent of red coloring
Oxygen content
71
Low oxygen content creates a bluish appearance
Cyanosis
72
Many alterations in skin color signal certain disease states or even emotional states:
- Redness, or erythema
- Pallor, or blanching
- Jaundice or yellow cast
- Bronzing
- Black-and-blue marks, or bruises
73
embarrassment (blushing), fever, hypertension, inflammation, or allergy
Redness, or erythema
74
fear, anger, and certain other types of emotional stress; may also signify anemia or low blood pressure.
Pallor, or blanching
75
usually signifies a liver disorder, in which yellow bile pigments accumulate in the blood and are deposited in body tissues
Jaundice or yellow cast
76
a sign of Addison’s disease; or a pituitary gland tumors that inappropriately secrete melanocyte-stimulating hormone (MSH)
Bronzing
77
hematomas
Black-and-blue marks, or bruises
78
Skin appendages include:
1. Hair and hair follicles
2. Nails
3. Sweat glands
4. Sebaceous (oil) glands
79
functions of hair and hair follicles:
- sense insects on the skin before they bite or sting us
- hair on the scalp guards head against physical trauma, heat loss, and sunlight.
- eyelashes shield the eyes, and nose hairs filter large
particles like lint and insects from the air we inhale
80
Produced by the hair bulb
hair
81
Consists of hard keratinized epithelial cells
hair
82
- tougher and more durable
- individual cells do not flake off
hair
83
provide pigment for hair color
Melanocytes
84
three layers of the hair shaft:
central medulla, cortex, cuticle
85
consists of large cells and air spaces
central medulla
86
the only part of the hair that contains soft keratin
(absent in fine hairs)
central medulla
87
surrounds medulla and has several layers of flattened cells
cortex
88
- on outside of cortex
- single layer of cells
- overlapping one another like shingles on a roof
Cuticle
89
the deep end of the follicle
hair bulb
90
knot of sensory nerve endings wrapping
each hair bulb
hair follicle receptor, or root hair plexus
91
contains a knot of capillaries that supplies nutrients to the growing hair and signals it to grow
hair papilla
92
actively dividing area of the hair bulb that produces the hair
hair bulge
93
pulls the hair follicle upright and dimples the skin surface to
produce goose bumps in response to cold temperatures or fear
arrector pili muscle
94
3 Structures of a Hair
central medulla, cortex, cuticle
95
Structure of a Hair Follicle
- hair bulb
- hair follicle receptor, or root hair plexus
- hair papilla
- hair bulge
- arrector pili muscle
96
Types and Growth of Hair
vellus hair and terminal hair
97
pale, fine body hair of children and adult
females
vellus hair
98
coarser, longer hair of the eyebrows and
scalp, also darker
terminal hair
99
terminal hairs grow in response to the stimulating effects of
androgens
100
phases of hair growth cycle
anagen (active growth phase), catagen (transition phase), telogen (resting phase)
101
permanent hair removal can only occur during this active growth phase
anagen (3-10 years)
102
club hair transitions upwards towards skin pore and dermal papilla begins to separate from follicle
catagen (2-3 weeks)
103
dermal papilla fully separates from follicle
telogen (3-4 months)
104
dermal papilla moves upwards to meet hair follicle once again and hair matrix begins to for new hair
return to anagen
105
hair growth cycle
1. permanent hair removal can only occur during this active growth phase
2. club hair transitions upwards towards skin pore and dermal papilla begins to separate from follicle
3. dermal papilla fully separates from follicle
4. dermal papilla moves upwards to meet hair follicle once again and hair matrix begins to for new hair
106
faster shedding of hair leading to hair thinning and some
degree of baldness
alopecia
107
By age 35, noticeable hair loss occurs in _____ of men, and by age 60 that number jumps to _______
40%; 85%
108
is a genetically determined, sex-influenced condition
Male pattern baldness
109
a drug used to reduce high blood pressure, has the interesting side effect in some bald men (and balding women) of stimulating hair regrowth
Minoxidil (rogaine)
110
factors affecting thinning of hair and baldness
- acutely high fever
- surgery
- severe emotional trauma
- certain drugs (excessive vitamin A, some antidepressants and blood thinners, anabolic steroids, and most chemotherapy drugs)
111
_______________________________________ lead to hair thinning
Protein-deficient diets and lactation
112
the immune system attacks the follicles and the hair
falls out in patches
alopecia areata
113
- scalelike modification of the epidermis
- clear protective covering on the dorsal surface of the distal part of a finger or toe
- useful as “tools” to help pick up small objects or
scratch an itch
Nails
114
nails (like hairs) contain
hard keratin
115
responsible for nail growth
nail matrix
116
proximal nail fold that projects onto the nail body
Eponychium
117
skin folds overlapping proximal and lateral borders of the nail
nail folds
118
proximal nail fold projecting onto the nail body
cuticle or eponychium-
119
free edge of the nail where dirt and debris tend to accumulate
Hyponychium
120
yellow-tinged nails
may indicate a respiratory or thyroid gland disorder
121
thickened yellow nails
may signal a fungus infection
122
outward concavity of the nail
may signal an iron deficiency
123
horizontal lines (Beau’s lines)
may hint of malnutrition
124
Widely distributed in skin
Sweat glands
125
two types of sweat glands
- Eccrine and Apocrine
126
eccrine glands are also called
merocrine sweat glands
127
- abundant on the palms, soles of the feet, and forehead
- simple, coiled, tubular gland
Eccrine glands
128
duct extends to open in a funnel shaped pore at the
skin surface
Eccrine glands
129
a hypotonic filtrate of the blood that passes through the secretory cells of the sweat glands
sweat
130
- with some salts (mostly sodium chloride), vitamin C, antibodies, a microbe-killing peptide dubbed dermcidin
- traces of metabolic wastes (urea, uric acid, and ammonia)
sweat
131
pH of sweat
between 4 and 6
132
sympathetic division of the autonomic nervous system regulates
sweating
133
sweat is released by
exocytosis
134
largely confined to the axillary and anogenital areas
Apocrine glands
135
apocrine glands produces
sweat, plus fatty substances and proteins
136
- Most with ducts that empty into hair follicles
- Glands are activated at puberty
Apocrine glands
137
activated by sympathetic nerve fibers during pain and stress
Apocrine glands
138
Modified Apocrine Glands
Ceruminous glands and Mammary glands
139
found in the lining of the external ear canal
Ceruminous glands
140
Ceruminous glands secretion mixes with sebum produced by nearby sebaceous glands to form a sticky, bitter substance called
cerumen or earwax
141
secrete milk
Mammary glands
142
- simple branched alveolar glands
- found all over the body except in the thick skin of the palms and soles
Sebaceous (oil) glands
143
sebaceous glands secrete an oily substance called
sebum
144
accumulated sebum blocks a sebaceous gland duct
Whitehead
145
oxidized and dried whitehead (darkens)
Blackhead
146
active inflammation of the sebaceous glands accompanied by “pimples” (pustules or cysts)
acne
147
caused by bacterial infection, particularly by staphylococcus
acne
148
acne is caused by bacterial infection, particularly by ___________________
staphylococcus
149
overactive sebaceous glands can cause, sloughed off oily scales
Seborrhea
150
Functions of the Integumentary System
1. Protection
- Chemical Barrier
- Physical Barriers
- Biological Barriers
2. Body Temperature Regulation
3. Metabolic Functions
4. Blood Reservoir
5. Excretion
151
acid mantle, dermcidin in sweat, bactericidal substances in sebum, natural antibiotics called ______________- punch hole in bacteria
defensins
152
- acid mantle
- dermcidin in sweat
- bactericidal substances in sebum
- natural antibiotics called defensins- punch hole in bacteria
Chemical Barrier
153
Substances that do penetrate the skin in limited amounts include
- Lipid-soluble substances, such as oxygen, carbon dioxide,
fatsoluble
- vitamins (A, D, E, and K), and steroids (estrogens)
- Oleoresins of certain plants, such as poison ivy and poison oak
- Organic solvents, such as acetone, dry-cleaning fluid, and paint thinner, which dissolve the cell lipids
- Salts of heavy metals, such as lead and mercury
- Selected drugs (nitroglycerine, nicotine, seasickness
medications)
Physical Barrier
154
Substances that do penetrate the skin in limited amounts include
- Lipid-soluble substances, such as oxygen, carbon dioxide,
fatsoluble
- vitamins (A, D, E, and K), and steroids (estrogens)
- Oleoresins of certain plants, such as poison ivy and poison oak
- Organic solvents, such as acetone, dry-cleaning fluid, and paint thinner, which dissolve the cell lipids
- Salts of heavy metals, such as lead and mercury
- Selected drugs (nitroglycerine, nicotine, seasickness
medications)
155
- Dendritic cells of the epidermis-act as antigen “presenters.”
- Dermal macrophages
- DNA-absorb UV radiation and transfer it to the atomic nuclei
Biological Barrier
156
cutaneous receptors are classified as
exteroceptors
157
allow us to become aware of a caress or the feel of our clothing against our skin
Tactile (Meissner’s) corpuscles & tactile discs
158
alert us to bumps or contacts involving deep pressure
Lamellar (Pacinian) corpuscles
159
report on wind blowing through our hair and a playful tug
on a pigtail
Hair follicle receptors
160
sense painful stimuli (irritating chemicals, extreme heat or cold, and others)
Free nerve endings
161
modified cholesterol molecules are converted to a
vitamin D precursor
162
Keratinocyte enzymes can
- “Disarm” many cancercausing chemicals that penetrate the epidermis
- Convert some harmless chemicals into carcinogens
- Activate some steroid hormones—for instance, they can transform cortisone applied to irritated skin
163
dermal vascular supply can hold about 5% of the body’s entire blood volume
Blood reservoir
164
- Nitrogenous waste products (ammonia, urea, and uric acid) in sweat
- NaCl excretion
Excretion
165
abnormal cell mass
Cancer
166
two types of cancer
Benign and Malignant
167
Does not spread (encapsulated)
Benign
168
Metastasized (moves) to other parts of the body
Malignant
169
is the most common type of cancer
skin cancer
170
- Least malignant
- Most common type
- Arises from stratum basale
Basal cell carcinoma
171
- Arises from stratum spinosum
- Metastasizes to lymph nodes
- Early removal allows a good chance of cure
Squamous cell carcinoma
172
- Most deadly of skin cancers
- Cancer of melanocytes
- Metastasizes rapidly to lymph and blood vessels
- Detection uses ABCD rule
Malignant melanoma
173
Detection uses ___________ for recognizing melanoma
ABCD rule
174
ABCD Rule
A = Asymmetry, two sides of pigmented mole do not match
B = Border irregularity, borders of mole are not smooth
C = Color, different colors in pigmented area
D = Diameter, spot is larger then 6 mm in diameter
175
- tissue damage inflicted by intense heat, electricity, radiation, or certain chemicals
- denature cell proteins and kill cells in the affected areas
Burns
176
leads to dehydration and electrolyte imbalance, and then renal failure (kidney shutdown) and circulatory shock (inadequate blood circulation due to reduced blood volume)
Burns
177
kidney shutdown
renal failure
178
inadequate blood circulation due to reduced blood volume
circulatory shock
179
In general, burns are considered critical if any of the following conditions exists:
- Over 25% of the body has second-degree burns
- Over 10% of the body has third-degree burns
- There are third-degree burns of the face, hands, or
feet
180
only the epidermis is damaged. Symptoms include localized
redness, swelling, and pain
1st-degree burn
181
symptoms of 1st-degree burn
redness, swelling, and pain
182
injure the epidermis and the upper region of the dermis. Symptoms mimic those of first-degree burns, but blisters
also appear.
2nd-degree burn
183
symptoms of of 2nd-degree burn
mimic those of first-degree burns, but blisters also appear.
184
Appears graywhite, cherry red, or blackened, and initially
there is little or no edema; not painful.
3rd-degree burn
185
keratinocytes undergo almost continuous mitosis in response to prompting by
epidermal growth factor
186
a peptide produced by various cells throughout the body
epidermal growth factor
187
is accelerated in body areas regularly subjected to friction, such as the hands and feet
cell production and keratin formation
188
persistent friction causes a thickening of the epidermis called a
callus
189
functions as a sensory receptor for touch
tactile or Merkel disc
190
eccrine sweat glands are abundant on
the palms, soles of the feet and forehead
191
microbe-killing peptide
dermcidin
192
apocrine sweat glands are activited by __________________ during pain and stress
sympathetic nerve fibers
193
force sebum out of the hair follicles to the skin surface
arrector pili contractions
