Integument Flashcards
1
Q
Basic layers of skin
A
epidermis, dermis, hypodermis
2
Q
Basic functions of integument
A
Protection Thermoregulation Sensory organ Metabolic Excretion of excess H20, salt, and nitrogenous metabolic wastes through sweating
3
Q
Thick skin
A
Palms of hands and soles of feet
No hair follicles
4
Q
Thin skin
A
skin other than palms and soles
thinner epidermis, hair follicles —with some exception
5
Q
Keratinocytes produce
A
keratin
6
Q
Epidermis
A
stratified squamous epithelial cells
7
Q
Cells accumulate more keratin as they migrate from
A
basal layer
8
Q
epidermis requires ______ days for cells to mature and desquamate
A
25-50
9
Q
Protection portion of integument functions
A
mechanical thermal chemical UV radiation dehydration
10
Q
Thermoregulation portion of integument functions
A
vascular network in dermis, sweat glands
11
Q
Sensory portion of integument
A
touch, temperature, pain
12
Q
metabolic portion of integument
A
vitamin D3 synthesis in epidermis. Energy storage (fat-triglycerides-hypodermis)
13
Q
Name the epidermal layers
A
Stratum basale (germinativum) Stratum spinosum Stratum granulosum Stratum lucidum Stratum corneum
14
Q
Stratum basale (germinativum) is compose of a
A
single layer of columnar to cuboidal cells
15
Q
Stratum basale contain numerous
A
intermediate filaments (tonofilaments)
16
Q
In stratum basale, hemidesmosomes bind cells to
A
basal lamina
17
Q
In stratum basale, desmosomes on the
A
lateral and upper surface
18
Q
Within the stratum spinosum layer of epidermis, the cells are
A
cuboidal, polygonal, to slightly flattened
19
Q
Cell processes of stratum spinosum is filled with
A
intermediate filaments and terminate with desmosomes
20
Q
(in stratum spinosum), cells accumulate fibrillar protein (cytokeratin)-aggregate to form
A
tonofibrils
21
Q
________ figures are also present in the stratum spinosum layer
A
“mitotic” figures
22
Q
This layer is composed of 3-5 layers of flattened polygonal cells
A
stratum granulosum
23
Q
cytoplasm of stratum granulosum has what type of granules
A
basophilic keratohyaline granules
24
Q
keratinosomes are
A
lamellar granules formed by lipid bilayers which fuse with cell membrane and discharge contents into intracellular spaces of the S. granulosum
25
(Stratum granulosum) the glycolipid acylglucoceramide serves as a
penetration barrier to foreign material and to maintain hydration of the body
26
Stratum lucidum can only be found in
thick skin, but not evident in all thick skin
27
Stratum lucidum is a thin layer of
eosinophilic, newly keratinized cells
28
Cells of stratum lucidum contain no organelles but do contain_______
eleidin (transformation product of keratohyalin)
29
Stratum corneum
15-20 layers of flattened non nucleated cells filled with keratin
30
Within stratum corneum, dead flattened cells are called
squames
31
How does skin heal?
If epidermis is injured, surrounding basal cells migrate and divide to cover the wound.
32
This vitamin is necessary for proper skin healing because it is needed for keratinocyte differentiation
Retinol (Vitamin A)
33
First degree burns extend to which layer of epidermis
1st degree burns extends down to S. lucidum
34
Second degree burns extent dow to
S. basale
35
3rd degree burns go down into
dermis
36
protein that aggregates keratin filaments
Filaggrin
37
If epidermis is injured....
surrounding basal cells migrate and divide to cover the wound
38
Kerationcyte differentiation
Different keratins are expressed as keratinocytes differentiate (from basal layer to s.spinosum to s.granulosum).
39
In s. granulosum, _________ are secreted to form multilayered lipid layer on the outside of the cell membrane
glycolipids
40
In the s. corneum, a protein complex of_______-_____ ______-____-_____ complex and keratin-filagrin aggregates link to the cytoplasmic side of the membrane
involucrin-small proline-rich-loricrin complex
41
(melanocytes) pigment producing cells of S. basal are derived from
neural crest
42
melanocytes
pigment producing cells of S. basal derived from neural crest
43
Lack of cortisol from the adrenal cortex causes
overproduction of ACTH---increases skin pigmentation (Addison's disease)
44
In albinism, melanocytes do not make
melanin
45
Melanocyte cytoplasm is _____ dense than neighboring keratinocytes
Melanocyte cytoplasm is less dense than neighboring keratinocytes
46
What enzyme is needed for melanin synthesis
tyrosinase
47
Loss of melanocytes
depigmentation (vitiligo)
48
Melanin formation occurs within
melanosomes
49
melanosomes are derived from
Golgi Apparatus
50
melanocytes rest on basal lamina and send cell processes into the
S. spinosum
51
Melanocytes distribute melanin to other cells and hair via processes. What is this process known as
Cytocrine secretion
52
In melanocytes, pigment granules are exocytosed and endocytosed by
keratinocytes
53
star shaped cells-- mainly in S. spinosum, occasionally in dermis near blood vessels
Langerhan's cells
54
Langerhan's cells can migrate out of epidermis to ______ _____ and present _______ to T cells and also differentiate into activated endothelial cells
Langerhan's cells can migrate out of epidermis to lymph nodes and present antigens to T cells and also differentiate into activated endothelial cells
55
Langerhans' cells do not form ________ ___________ with other cells
Langerhans' cells do not form desmosomal attachments with other cells
56
Langerhans cells are derived from
bone marrow- macrophage lineage
57
Contents of Langerhans' cells
Has unique membrane-bound, rod-like to racquet shaped granules, which contain proteins necessary for antigen uptake
58
Merkel's cells are primarily located in
thick skin of palms and soles
59
Tactile epithelioid cell associated with sensory nerve ending
Merkel's cells
60
Merkel cells are also involved in
2pt discrimination
61
composed of connective tissue--- supports epidermis and binds it to the subcutaneous tissue
dermis
62
cytoplasm of Merkel's cells contain small dense granules that may be related to
catecholamine containing granules of neurosecretory cells
63
the base of Merkel's cells are in contact with the
peripheral neuron terminal
64
surface of dermis interdigitates with epidermis via
dermal papillae
65
Epidermal counterpart to dermal papillae =
epidermal ridges or rete ridges
66
anchoring fibrils extend from the______ ______ and terminate in _______ _______ to bind the dermis to the epidermis
anchoring fibrils extend from the basal lamina and terminate in anchoring plaques to bind the dermis to the epidermis
67
Basic function of anchoring fibrils
binds the dermis to the epidermis
68
Reticular layer of dermis is composed of
dense irregular CT--- thicker than papillary layer
69
Dermis has
follicles, sweat and sebaceous glands, and nerves
70
outermost layer of dermis contains
loose connective tissue( fibroblasts, mast cells, and macrophages may be present)
71
extensive capillary network in the papillary layer of dermis functions in
thermoregulation
72
deeper continuation of the dermis
hypodermis
73
hypodermis is composed primarily by
loose connective tissue and adipose tissue
74
Pacinian corpuscles
pressure/vibration sensors found near dermis-hypodermis junction
75
Hair follicle is an invagination of the epidermis that terminates in _____ _____
hair bulb
76
dermal papilla projects into
hair bulb
77
epidermal cells covering the dermal papilla form the
hair root
78
the hair root produces and is continuous with the
hair shaft
79
Some cells around the papilla differentiate into fusiform. What are fusiform and what do they form?
heavily keratinized cells, form the hair cortex
80
Cells more peripheral in the hair root produce the
hair cuticle
81
most peripheral root cells produce the
internal and external root sheath
82
hair follicles are separated from the dermis by a thickened basal lamina called the
glassy membrane
83
arrector pili muscles
smooth muscle bundles extending from dermis papillary layer to hair follicle connective tissue sheath
84
These glands are not found on palms and soles
sebaceous glands
85
Dead cells + cell contents =
sebum
86
Eccrine (merocrine) sweat glands
simple coiled tubular gland -- duct opens onto skin surface. receive cholinergic nerve fibers
87
Dark cells secrete
glycoproteins
88
clear cells secrete
H20 and electrolytes into intercellular canaliculi
89
Sudoriferous (Sweat) Glands contain
myoepithelial cells (contractile), dark cells (mucoid, pyramidal cells) and clear cells (devoid of secretory granules, but have abundant glycogen)
90
the ducts of apocrine cells open into
hair follicles
91
Apocrine glands are present where?
axillary, areolar, and anal regions
92
What mechanism of secretion do apocrine sweat glands have?
merocrine
93
what type of nerve fibers do apocrine glands receive?
Apocrine glands receive a adrenergic nerve fibers
94
Apocrine glands contain only one kind of ______ ____ and produce viscous protein containing secretion
secretory cell
95
What are nails?
Plates of keratinized epithelial cells
96
Nail root is embedded in
fold of skin
97
The stratum corneum of the epithelium over the nail root forms the
eponychium (cuticle)
98
Nail plate rests on a bed of epidermis called the
nail bed
99
nail bed contains only a
S. basale and S. spinosum
100
Where does the nail plate arise from?
Nail plate arises from the nail matrix
101
the nail matrix extends from the nail root to the
lunula (white crescent and the base of the nail)
102
Albinism
little melanin production. Vision problems due to abnormal retina development and abnormal nerve connections between eye and brain
103
melanocytes are destroyed-patchy pigmentation
vitiligo
104
"liver spots"
freckles due to being in the sun (older individuals)
105
Actinic keratosis
precancerous condition. thick scaly patches of skin
106
Basal cell carcinoma
(90% of all skin cancers) slow growing and treatable if found early
107
Squamous cell carcinoma
often develop from sun damaged areas (actinic keratosis due to sun damage)
108
Malignant melanoma is derived from
melanocytes and is hard to treat once metastasized
109
Psoriasis
Immune-mediated, genetic disease. red scaly patches of skin due to inflammation and hyperplasia.
110
Individuals with psoriasis often have
joint problems (psoriatic arthritis)
