Integument Flashcards
1
Q
Integument Accessory structures
A
Hair Nails Various glands Muscles Nerves
2
Q
Two principal parts
A
Epidermis (superficial)
Dermis (deeper, thicker)
3
Q
What is NOT part of the skin?
A
hypodermis (aka subcutaneous)
consisting of areolar and adipose tissue
4
Q
Composed of epithelial tissue
A
epidermis
5
Q
Composed of dense irregular tissue?
A
Dermis
6
Q
Specific functions of the skin
A
Thermoregulation
Protection from the internal environment
Cutaneous sensation
Excretion
Synthesis of Vit. D
Reservoir for blood
Absorbs substances
7
Q
____ traps heat?
A
Hair
8
Q
Epidermis is composed of _________.
A
Keratinized stratified squamous epithelium
9
Q
4 major cells of epidermis
A
Keratinocytes
Melanocytes
Langerhans cells
merkel cells
10
Q
Most of the epidermal cells in the skin are _____
A
keratinocytes
11
Q
Formed when new cells produced by mitosis become filled with keratin, a tough, fibrous protein
A
keratinocytes
12
Q
waterproofs the skin and Helps protect the skin and underlying tissues from heat, microbes, and chemicals
A
keratinocytes
13
Q
Organelle called a _____ produces the pigment melanin, a brown-black pigment that contributes to skin color and absorbs damaging ultraviolet light
A
melanosome
14
Q
Projections from _____ extend between keratinocytes, and transfer melanin granules to them.
A
melanocytes
15
Q
The melanin granules then cluster over the ____ on the side toward the skin surface, shielding nuclear DNA from UV light
A
nucleus
16
Q
The melanosomes of melanocytes synthesize melanin from the amino acid ____ in the presence of the enzyme _____
A
tyrosine
tyrosinase
17
Q
Participate in immune responses to microbes that invade the skin (they are therefore “immune” cells)
A
Langerhans Cells
18
Q
Type of dendritic cell, that present antigens
A
Langerhans
19
Q
Reside in the deepest layer of the epidermis where they contact the flattened processes of tactile discs (AKA ___ discs), which are a type of sensory neuron (nerve cell)
A
merkel cells
merkel discs
20
Q
Together the ___ cells and tactile discs function in the sensation of touch
A
Merkel
21
Q
Layers of skin from top to bottom
A
Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale
22
Q
Mnemonic—Come, let’s get some beer
A
Corneum Lucidum Granulosum Spinosum Basale
23
Q
The ____ is present only where exposure to friction is greatest, such as the fingertips, palms, and soles.
A
stratum lucidum
24
Q
Deepest layer of the epidermis and mostly keratinocytes, a few melanocytes and Merkel cells
A
Stratum Basale
25
Keratinocytes have intermediate filaments called _____ composed of a protein that will later form keratin
Stratum Basale
tonofilaments
26
Keratinocytes continuously undergo ____, thereby forming new skin cells
mitosis
27
Just superficial to the stratum basale
Stratum Spinosum
28
8-10 layers of keratinocytes; few Langerhans cells
Spinosum (cells are still alive, some divide)
29
Here the older cells start to flatten
Spinosum
30
3-5 layers of flattened keratinocytes
Granulosum
31
Transition between the deeper living cells and the more superficial dead cells
Granulosum
32
Lamellar granules release a waterproofing lipid solution in?
Granulosum
33
3-layers of flattened, dead keratinocytes filled with keratin
Lucidum
| fingertips, palms, soles
34
25-30 layers of flattened, dead cells
Corneum
35
Between cells, lipids from lamellar granules provide water proofing
Corneum
36
Cells are continuously sloughed off and replaced by cells from deeper strata
Corneum
37
Dense irregular connective tissue; collagen and elastic connective tissue
dermis
38
Dermis' contents
bood vessels
nerves
glands (sebaceous and sudoriferous)
hair follicles
Arrectores pilorum
39
Dermis divided into two componentss
papillary region (superficial)
reticular region (deeper)
40
____ greatly increase papillary region surface area
Dermal papillae
41
Receptors present in papillary region
Touch corpuscles (Meissner corpuscles) for touch/light touch
Free nerve endings with no apparent structural specialization that give rise to sensations of warmth, coolness, pain, tickle, itch
42
More elastic and collagen
Reticular regions
43
Reticular regions has these features
adipose cells, hair follicles, nerves, sebaceous glands, and sudoriferous glands
44
Hypodermis contains:
Fat
Fibers that attach the dermis to deeper tissues
Larger blood vessels
Sensory receptors: Pacinian corpuscles (lamellated corpuscles) sense pressure
45
corpuscles that sense pressure
Pacinian
46
Commonly called fingerprints
epidermal ridges
47
Epidermal ridges develop during the ___ fetal months
3rd and 4th
48
Skin color due to combination of:
Melanin
Carotene
Hemoglobin
49
The amount and expression of _____ are genetically determined, and are associated with the classic races of humans
melanin and carotene
50
Differences in skin color among different races are mainly due to the amount of pigment the melanocytes produce and distribute, since the ____ of melanocytes is about the same in all races
number
51
Exposure to UV light increases the enzymatic activity of ____, leading to increased melanin production, which gives the skin a tanned appearance and further protects the body against UV radiation
melanosomes
52
__ is a yellow-orange pigment that is a precursor to vitamin A, which is used to synthesize pigments needed for vision
Carotene
53
Sebaceous glands: in the dermis; secrete sebum (oil) into a ___
hair follicle
54
___ is the superficial portion of the hair
Shaft
55
Shaft and root have three layers:
medulla, cortex, cuticle
56
Surrounding the root of the hair is a hair follicle that has an external root sheath which is a downward continuation of the ___
epidermis
57
Hair is composed of dead, keratinized cells bonded by ___
proteins
58
Root of the hair is in the ___
dermis
59
Growth is by division of cells at the base of the hair follicle whereby new cells produced by mitosis in the hair matrix push the growing hair through the ____
pilary canal
60
The ___ is an enlargement at the base of the hair follicle
bulb
61
Within the bulb (hair) is a germinal layer of cells called the ____ which arises from the stratum basale, and is the site of cell division that produces the hair
matrix,
62
A bundle of smooth muscle called the ____, along the sebaceous glands which are associated with hair follicles
arrector pili
63
Under physiologic or emotional stress (cold, fright) autonomic nerve endings stimulate _____ muscles to contract, causing “goose bumps
arrectores pilorum
64
Groups of dendrites and nerve fiber endings that form a network around a hair follicle
Hair root plexus
65
Act as receptors to generate nerve impulses when hair shafts are moved. Shaft of hair acts like a fulcrum.
Hair root plexus (snesitive to touch and movt of hair)
66
Each nail consists of a nail body, a free edge, and a ____
nail root
67
Nail body is the portion of the nail that is ____
visible
68
The ___ is the whitish, crescent-shaped area of the proximal end of the nail.
lunula
69
The epithelium deep to the nail root is the
nail matrix
70
Cells of the ____divide mitotically to produce growth
nail matrix
71
Superficial cells of the matrix are transformed into nail cells, and the older, harder cells are pushed along the ____ toward the fingertip
stratum basale
72
From sebaceous glands, sebum is an oily substance that:
Keeps hair from drying
Prevents excessive evaporation of water from the skin
Inhibits growth of some bacteria
73
Two main types of sweat (sudoriferous) gland
Eccrine and apocrine glands
74
The more common, found most places on skin, function in thermoregulation (aka merocrine sweat glands)
Eccrine
75
Found in association with hair that develops at puberty (axilla, groin, beard)
Apocrine sweat glands
76
In ___, keratinocytes divide and move more quickly than normal from the stratum basale to the stratum corneum, and are shed prematurely
psoriasis
77
Most common skin cancers
Basal cell carcinomas (the most common)
Squamous cell carcinomas
Malignant melanomas (the least common overall, and most life-threatening)
78
In most cases, the melanocytes are unable to synthesize ___
tyrosinase
79
___ is the partial or complete loss of melanocytes from patches of skin
Vitiligo
May be an autoimmune disorder in which the melanocytes are attacked and killed. There is also an apparent genetic link
80
___ is due to the fact that hemoglobin that is depleted of oxygen looks deep, purplish blue
Cyanosis
81
Caused by a buildup in the blood of the yellow pigment bilirubin
jaundice
82
Erythema caused by ___ of capillaries in the dermis with blood due to
engorgement
83
A form of scarring of the skin caused by tearing of the dermis
Striae (streaks)
84
Partial or complete lack of hair
Alopecia
85
____is an inflammation of the skin characterized by redness, itching, and swelling, and caused by exposure of the skin to chemicals that bring about an allergic reaction
Contact dermatitis
86
___ occurs following superficial wounds that affect only the epidermis.
Epidermal wound healing
87
___ occurs when an injury extends to the dermis and subcutaneous layer
Deep wound healing
loss of some function and scar tissue is the rule
88
____ cells at the margins of the wound break contact with the basement membrane and migrate
(epidermal wound healing)
Basal
89
When basal cells contact each other, they stop migrating, called ___ and Mitosis of basal cells is stimulated
(epidermal wound healing)
contact inhibition
90
A blood clot forms and binds wound edges
Blood flow is increased, blood vessels become more permeable
WBCs and mesenchymal cells migrate to the area
(deep wound healing)
Inflammatory phase
91
Epithelial cells migrate beneath the scab and bridge the wound
Fibroblasts migrate into the wound and begin to produce collagen fibers
(deep wound healing)
Migratory phase
92
Growth of epidermal cells beneath the scab
Increase in the amount of collagen
Regeneration of blood vessels
(deep wound healing)
Proliferative phase
93
Scab is lost
Collagen fibers become more organized, fibroblast numbers decrease, blood vessels are restored to normal
(deep wound healing)
Maturation phase
94
A ___ is tissue damage caused by excessive heat, electricity, radioactivity, or corrosive chemicals that destroy (denature) the proteins in the skin cells
burn
First degree
Second degree
Third degree
95
Involves only the epidermis
Characterized by mild pain and erythema, but no blisters
Skin functions remain intact
First degree burn
96
Accompanying pain and damage may be lessened by immediately flushing with cold water
Will heal in a few (3 – 6) days, and may be accompanied by flaking or peeling
Example is a mild sunburn
First degree burn
97
Destroys a portion of the epidermis and possibly parts of the dermis
Characterized by pain, redness, blister formation, and edema
Some skin functions are lost
Second degree burns
98
Associated structures (hair follicles, sebaceous glands, sweat glands) are not usually injured
Generally heals in a few (3 – 4) weeks, if there is no infection
Scarring may result
Second degree burns
99
Destroys a portion of the epidermis as well as the underlying dermis and associated structures
Skin functions are lost
Vary in appearance from marble-white to mahogany to charred, dry wounds
Third degree burns
100
Is marked edema, and the burned region is numb due to destruction of sensory nerve endings
Regeneration is slow; grafting may be required
Also termed full-thickness burn
Third degree burns
101
One 9 = total head and neck
One 9 = total each upper limb {18% for both}
Two nines for each front and back of torso (including buttocks)
One 9 each anterior and posterior lower limb {18 entire left lower limb, 18 entire right lower limb}
Remaining 1% is perineum
Rule of nines
