Anatomy ch 6- Integumentary system Flashcards
1
Q
Covers body and consists of the skin and accessory tissues (hair, nails, sweat/oil glands, sebaceous glands)
A
Integumentary system
2
Q
Integument
A
- Cuteaneous
2
Q
Dermatology
A
Study of the skin
3
Q
Epidermis
A
stratified squamous epithelium
4
Q
Dermis
A
The deep layer of the skin; composed of dense, irregular connective tissue
5
Q
Hypodermis
A
Not part of the integumentary system
deep to the dermis
subcutaneous layer
alveolar and CT
6
Q
function of integumentary system
A
protection
sensation
vitamin D production
immunity
body temp regulation
excretion
7
Q
What are Keratinocytes?
A
main cell type of epidermis
produce keratin intermediate filaments
provide structure to the hair, skin, and nails
Waterproofing (protective function)
keratinizing tissue (dry); nonkeratinizing tissue (wet)
8
Q
Melanocytes
A
produce pigments (eumelanin/pheomelanin) giving skin and hair color
protects from UV rays
9
Q
Merkel cells
A
Tactile cell- stratum basale
- few in number
- sensitive to touch- when compressed, release chemicals, stimulate sensory nerve endings
connected to sensory neuron
10
Q
What are the layers of the epidermis?
A
Stratum Basale, Stratum spinosum, stratum lucidum, stratum corneum Stratum granulosum
11
Q
The deepest layer of the epidermis consisting of stem cells capable of undergoing cell division to form new cells
single layer of newly produced cuboidal cells
contains melanocytes and epidermal ridges
A
Stratum basale
12
Q
8-10 rows of keratinocytes
accumulation of keratohyalin, lamellar bodies
A
Stratum spinosum
13
Q
Stratum granulosum
A
3-5 rows of keratinocytes
large amounts of keratohyalin are produced
contain many chemical granules, stain darker on histology
14
Q
Stratum lucidum
A
layer of dead keratinocytes, only in thick skin (palms, soles)
contains translucent protein eleidin
15
Q
stratum corneum
A
15-30 layers of dead keratinocytes
lipid coating forms water resistant layer
16
Q
Is the epidermis vascular or avascular… why?
A
Avascular … no blood vessels
17
Q
What are the three variations of the epidermis?
A
Color, thickness, skin markings
18
Q
Thick skin
A
palms of hand/soles of feet
contains all 5 layers of epidermal strata
Has sweat glands; just no hair follicles or sebaceous (oil) glands
19
Q
Thin skin
A
Covers most of the body, lacks stratum lucidum, has sweat glands, hair follicles, and sebaceous glands
20
Q
which layer of the epidermis connects to the dermis?
A
Stratum basale
21
Q
How does the epidermis provide protection?
A
- the dry surface does not allow for the growth of most microorganisms
- Langerhans cells are found in all layers expect for stratum corneum
22
Q
***Langerhans cells act as?
A
- antigen-presenting cells
- first line of defense
- bind to foreign particles, drags it to a cell that can do something: macrophage/natural killer cell
23
Q
list the 3 color-producing pigments/proteins in skin
A
Hemoglobin, Melanin, Carotene
24
Hemoglobin
-oxygen-binding protein in erythrocytes (red blood cells)
-bright red color upon binding oxygen
25
Melanin
-dark pigment produced by melanocytes, transferred to keratinocytes
-amount in skin varies (heredity, UV exposure)(race/tanning
26
Carotene
yellow-orange pigment acquired from some vegetables/ diet
27
Process of skin pigmentation
1. melanocytes produce melanin from tyrosine in specialized organelles (melanosomes)
2. melanosomes are transferred to keratinocytes upon stimulation
3. melanosomes in keratinocytes produce melanin granules to contribute to skin pigmentation
28
factors affecting pigmentation
1. Type of melanin produced
2. How much the melanosomes are filled with melanin granules prior to transfer
3. Number and size of melanosomes produced
4. How long the melanosomes persist in the keratinocytes
5. Degree of transfer within the dermis
29
How do you get a tan?
1. UV rays generate reactive oxygen
2. melanocytes excessively produce melanin
3. Skin pigmentations are generated
30
UV radiation causes?
- immune suppression
- DNA damage
- oxidative damage
31
Carcinogenesis
development of cancer
32
Tactile discs
Formed from Merkel cells
- located in stratum basale
- function as mechanorecpetors : signal from physical force
- associated w/fine touch and pressure
33
Free nerve endings are associated with?
Pain, itching, tickling
34
cells of the epidermis convert ____ to ____ in the presence of sun
7-denydrocholesterol to cholecalciferol (vitamin D3)
35
Vitamin D gets turned into.....?
Calcitriol
36
Calcitriol does what?
- increases calcium absorption in the small intestine
- increases bone mineralization
37
List the 3 skin markings
Nevus, Freckles, Friction ridges
38
Freckles
Yellowish or brown spots
Localized areas of increased melanocyte activity
39
Moles
Localized overgrowth of melanocytes
Should be monitored for changes suggesting malignancy (tumor, cancer)
40
Friction Ridges
Large folds and valleys of dermis and epidermis
fingerprints
41
Dermis
-below the epidermis
-made up of irregular dense CT proper
-has papillary and reticular layers
42
What other structures are present in the dermis?
Blood vessels
sweat glands
sebaceous glands
hair follicles
nail roots
sensory nerve endings
arrector pili
43
Papillary layer
- Loose connective tissue made up of
fine collagen and elastic fibers
- Associates with epidermis through
dermal papillae and epidermal ridges
- Contains blood/lymphatic vessels and
nerves that supply the epidermis
44
Functions of the papillary layer
- support epidermis
- regulate body temp
- provide OXYGEN to epidermis
45
reticular layer
Dense irregular connective tissue, densely-packed collagen fibers with some elastic fibers interspersed
- Toughest layer of skin
-Thick collagen bundles produce cleavage lines (e.g. palm of hand)
-Contains blood vessels, nerves, and other accessory structures
46
the dermis is made of
- collagen and elastic fibers oriented in parallel bundles at specific locations
47
Function of elastic fiber bundles
Resist stress during movement
48
Orientation indicated by lines of cleavage
- Incisions parallel to cleavage lines are more likely to heal quickly
- Incisions perpendicular to cleavage lines are more likely to open due to cut elastic fibers
49
If skin stretched beyond its capabilities:
- Some collagen fibers torn
- Stretch marks, striae
50
How does the dermis support the epidermis?
provides oxygen and nutrients
Maintains fluid balance
51
Meissner's corpuscles
LIGHT touch, pressure, vibration
52
Lamellated corpuscles
DEEP pressure and vibration
53
Ruffini corpuscles
pressure and skin distortion (stretching)
54
which layer (epidermis, dermis) regulates blood flow to the skin
dermis
55
deepest part of the integumentary system
dermis
56
T or F
the hypodermis is part of the integument
False, This layer is classified as subcutaneous layer, Not apart of the skin.
57
What is the hypodermis composed of?
-adipose and areolar connective tissue
-collagen and elastic fibers
-fibroblasts and adipocytes
-Contains larger blood vessels and nerves that supply the skin
58
what does the hypodermis do
-Connects skin to underlying tissue
-Serves as energy reserve (subcutaneous fat)
-common injection site (ex: insulin)
59
Functions of the hair:
-Protection against entrance of foreign substances into body
-Protection against UV radiation
-Sensory
60
where does hair grow from?
what does hair papilla contain?
what is the hair matrix responsible for?
-Hair grows from cells at the base of the follicle (hair bulb)
-Hair papilla contains connective tissue, blood vessels, and nerves
The hair matrix within the papilla is responsible for producing new hair
61
What 3 structures are apart of the hair shaft?
Medulla, cortex, cuticle
62
Medulla is ?
-very center
-Cells contain soft keratin
-Formed by cells closest to the hair matrix
63
Cortex?
- middle
- Cells contain hard keratin
- Formed by cells near the edge of the hair matrix
64
Cuticle
- Edge
- Cells contain hard keratin
- Formed by cells at the edge of the hair matrix
65
Vellus hairs
Fine hairs located over much of the body surface
66
Terminal
coarse hairs; some develop during puberty (pubes)
hair on head, lashes, brows
67
Lanugo hair
Fine, unpigmented, downy hair
- appears in last trimester of pregnancy '
- fetus develops in last trimester to insulate
68
What causes goosbumps?
contraction of arrector pili muscle
69
What are nails biologically?
scale-like modifications of the stratum corneum
70
Part of nail that gets cut off
no underlying capillaries
free edge of nail
71
translucent portion of the nail, extending from the nail root to the free edge; sometimes referred to as the nail body.
underlying capillaries
Nail plate
72
Portion of the living skin that supports the nail plate as it grows toward the free edge.
Nail bed
73
Lunula
The half-moon-shaped, whitish area at the base of a nail
74
- Secretes sebum (oily substance)
- Helps protect the surface of the skin (lubricant/bactericidal
- Prevents water loss and bacteria growth
- Play a role in thermoregulation
- Classified as holocrine glands
Sebaceous glands features and functions
75
Apocrine and Merocrine/eccrine are ____
Sudoriferous glands
76
- Localized mainly in armpits and pubic regions
- Secrete product into hair follicles
- Product secreted used by bacteria, contributing to odor
Apocrine sweat glands
77
Merocrine/eccrine
- Far more numerous
- Secrete product directly onto the skin surface (pores)
- Function in thermoregulation, secretion and protection
78
Ceruminous glands
Modified apocrine sweat glands
Located only in external ear canal
Secretions of waterproof earwax, cerumen:
- traps foreign material (bacteria)
- Lubricates acoustic meatus and eardrum
79
Mammary glands
Modified apocrine sweat glands of the breast
Only function in pregnant and lactating females
Produce milk
80
Albinism
- most commonly an autosomal recessive genetic disorder
- Results in low/no melanin production by melanocytes
- high incidence of eye pathology comorbidity
81
Alopecia areata
- Autoimmune skin disease
- T-lymphocytes attack and kill hair follicle cells
- Mechanism not fully understood
- Cannot be cured, but can manage symptoms
82
- Overgrowth/overproduction of terminal and vellus hairs on the entire body other than palms of hand/soles of feet
- Varies in severity & risk factors
- Severe = typically genetic mutation, grows "malignant down" on face
- Can be linked with cancer
Congenital terminal HYPERTRICHOSIS
83
- Major cause of accidental death
- Caused by heat, radiation, chemicals, sunlight, electrical shock
- Threat to life from fluid loss, infection, effects of burned tissue
Burns
84
involve epidermis and part of the dermis
- skin blisters, painful, & slight scarring
Second degree burn
85
Involve only epidermis, slight redness, & pain
First degree pain
86
Third degree burn
- Involve epidermis, dermis, and subcutaneous layer (hypodermis)
- Require hospitalization
- treatment for dehydration and infection
- Severe scarring
- May need debridement and skin graft
87
- Chronic autoimmune skin disease
- Keratinocytes attacked by T-lymphocytes
- Causes rapid overgrowth of new skin cells
- Patches of whitish, scaly skin on the epidermal surface
Symptoms: severe itching, pain, skin cracking
Treatments* Corticosteroids, UV light therapy, medications that interfere with skin cell production
Psoriasis features
symptoms
treatments
88
- Rare genetic skin disorder
- deletion mutation in the X chromosome = region that that codes for the enzyme steroid sulfatase
- responsible for removing sulfur from cholesterol = needed proper function of lipid barrier in stratum corneum & health of skin
- Absent enzyme results in excessively dry skin, polygon-shaped scale formation
X-LINKEDICHTHYOSIS
89
Skin cancer
- Generalized term used for multiple cancer types
- Characterized by cells that fail to die on signal, over proliferate, lose cellular function,
- Can metastasize and destroy tissue via inflammation
90
Basal cell carcinoma
- Most common type of skin cancer
- Cancer of basal cells in basal layer of the epidermis
- Most often occur on areas of skin that are exposed to the sun via UV radiation
- Most grow slowly and are curable
- Rarely spread beyond the initial tumor site
91
- AKA epidermoid carcinoma
- Affects squamous cells - mostly stratified squamous
- Usually faster growing than Basal Cell Carcinoma
Squamous cell carcinoma
92
- Cancer of melanocytes
- Typically most serious type of skin cancer
- Linked to UV radiation
- If metastasized, about 22% 5year survival rate
Melanoma
93
Antigen
Foreign particle
94
Eumelanin
Good for us!
brown/black pigment
UV Vis absorbing- doesn't allow it to go to nucleus
Antioxidant
95
Pheomelanin
Bad for us!
reddish-yellow pigment
Pro-oxidant
Phototoxic
96
majority of sensory cells are located?
In the dermis
97
****What is the top layer of skin? what is its epithelia?
Epidermis
stratified squamous
98
***What is the middle layer of skin?
What is the majority of its tissue?
Dermis
Dense irregular CT
99
Name 3 cells of the epidermis
Keratinocytes
Melanocytes
Merkel cells
100
What is the bottom layer of the epidermis?
What is the top layer of the epidermis?
Stratum Basale
Stratum Corneum
101
***Which layer is NOT present in THIN skin
Stratum lucidum
102
***Where can you find tactile discs?
Stratum Basale
103
***What is the function of free nerve endings?
detect pain, itching, tickling
104
***A cut that is parallel to a cleavage line will most likely heal
quickly
105
***What is the function of Pacinian/lamellated corpuscles?
Deep pressure and vibration
106
***A hair shaft contains an inner ____ region, an outer ____ region, and a layer of cuticle
Medulla; cortex
107
***Which hairs are smaller and softer in nature?
Vellus hairs
108
****Which integument glands secrete sweat?
****Which integument glands secrete cerumen?
Sudoriferous
Ceruminous
109
***Explain the difference between basal and squamous cell carcinoma
Basal cell carcinoma affects the basale cells in the basale layer; slow growing and curable; rarely spreads; encapsulated in a shell
squamous cell carcinoma affects stratified squamous and spreads quicker than basale cell carcinoma.
110
***Why does X-linked ichthyosis impact men more than women?
Because women have 2 X chromosomes, men only have 1.
111
***Which layer lies directly under the stratum granulosum ?
Stratum spinosum
112
***Which hairs are found on most of the body that are small & fine?
Vellus hairs
113
*** which layers of the skin are impacted by a second-degree burn?
Epidermis and Dermis
114
which glands secrete sweat directly onto the surface of the skin via pores?
Merocrine/ eccrine sudoriferous glands
