Chapter 5 Flashcards
(119 cards)
1
Q
the integumentary system consists of
A
the Skin and its
accessory structures, including hair, nails, and glands
2
Q
the skin is a ___________ membrane
A
cutaneous
3
Q
the skin is … (mass)
A
Largest organ in the
body, making up 10-15% of our total body weight and has 2
main components
4
Q
2 main components of the skin
Layers
A
- superficial epidermis
- deep dermis
5
Q
what is the superficial epidermis
What kinds of cells is it made of
A
Top layer of the skin
Consists of keratinized stratified
squamous epithelium resting on a basement membrane
6
Q
what is the deep dermis
What kinds of cells is it made of
A
Second layer, below the epidermis
Consists of loose connective tissue and
dense irregular connective tissue
7
Q
what are the accessory structures of the skin
A
- nails, hair, sweat glands
- oil producing sebaceous glands
8
Q
skin includes (not accessories or layers)
A
sensory neurons and receptors, and arrector pili muscles that attach to hair
9
Q
epidermis is ________ while the dermis is _________
A
avascular, vascularized
10
Q
below the dermis is the
A
hypodermis
11
Q
hypodermis aka
A
superficial fasia or subcutaneous tissue
12
Q
hypodermis is
A
- not part of the skin
- Includes loose connective and adipose tissue and is highly vascularized
13
Q
what is cellulite
A
Term used to describe the dimpled, or “orange
peel” appearance of the skin when the collagen bands form
around adipose tissue in the hypodermis
14
Q
functions of the integumentary system
A
- protection
- sensation
- thermoregulation
- excretion
- synthesis of vitamin d
15
Q
Integumentary System - protection
A
- mechanical trauma
- pathogens
- environment
- uv light
16
Q
Integumentary System - sensation
A
Sensory receptors in the skin are perceived as sensations by the nervous system
17
Q
Integumentary System -thermoregulation
A
maintenance with negative feedback loops
- stimulus
- receptor
- control center
- effector/response
- return to normal range
18
Q
Integumentary System - excretion
A
metabolic waste products
- lactic acid
- urea
eliminated as sweat
19
Q
Integumentary System - vitamin d
A
- Precursor compound of Vitamin D is in the deep cells of the epidermis
- When exposed to U V radiation, this compound is converted to Cholecalciferol, which enters the bloodstream
- Modified by the liver, then kidneys to form Calcitriol
20
Q
vitamin d synthesis aka
A
calcitriol synthesis
21
Q
epidermis is
A
Superficial part of the skin; Composed of several cells types and up to 5 layers
22
Q
layers of the epidermis are called
A
strata
23
Q
keratinocytes
A
- Make up approximately 95% of cells in the epidermis; Provide strength to the epidermis
- Manufacture Keratin, which is a fibrous protein that makes tissue strong and resistant to mechanical stress, aids in waterproofing, immune response, barrier formation
24
Q
what are other cells in the epidermis
A
- dendritic (Langerhans) cells
- tactile (merkel cells)
- melanocytes
25
what are dendritic cells
Phagocytes of the
immune system that protect the skin and deeper tissues
26
what are Langerhans
Phagocytes of the
immune system that protect the skin and deeper tissues
27
what are tactile cells
Sensory receptors that detect
light touch and differentiate shapes and textures;
Numerous in fingertips, lips, and the base of hairs
28
what are merkel cells
Sensory receptors that detect
light touch and differentiate shapes and textures;
Numerous in fingertips, lips, and the base of hairs
29
dendritic cells aka
langerhans
30
langerhans aka
dendritic cells
31
tactile cells aka
merkel cells
32
merkel cells aka
tactile cells
33
what are melanocytes
Produce melanin, which is an orange-red to
brown-black pigment (discussed in Module 5.4)
34
what is thick skin
Found on locations subject to more
mechanical stress, including the palms of the hands,
palmar surfaces of fingers, soles of the feet, and plantar
surfaces of toes
35
properties of thick skin
- Contains all 5 strata and a very thick stratum corneum
– Lacks hair follicles, but has numerous sweat glands
36
what is thin skin
found everywhere there is not thick skin
37
properties of thin skin
– No stratum lucidum and thinner stratum corneum
– Includes hair follicles, sweat and sebaceous glands
38
what are calluses
Additional layers of stratum corneum; Forms in
response to repeated pressure
39
what is the dermis
Deep part of the skin; Houses the blood
supply of the epidermis; Contains sensory receptors;
Anchors the epidermis in place; Divided into 2 layers
40
what are the 2 layers of the dermis
- papillary layer
- reticular layer
41
the dermis - papillary layer
Superficial layer of the dermis
* Makes up about 20% of the depth of the dermis
* Made of loose connective tissue
* At the dermis-epidermis junction, special collagen fibers
extend into the basement membrane to anchor the
epidermis; Repetitive trauma disrupts these fibers and
causes a fluid-filled pocket called a blister
* The surface of the papillary layer folds into projections that
push into the epidermis called Dermal Papillae
42
what do dermal papillae do
– Provide blood supply to the epidermis
– House Tactile (Meissner) Corpuscles
43
what are Tactile (Meissner) Corpuscles
respond to light
touch, and distinguish shape and texture of objects; Numerous in
fingertips, lips, face, and external genitalia
44
dermis - reticular layer
Deep layer of the dermis
* Made of dense irregular connective tissue, which strengthens the
dermis and allows it to stretch, and house Blood vessels, sweat
glands, hairs, sebaceous glands, and sensory receptors.
45
what are skin markings
Interactions between the epidermis and dermis
are visible as small lines in the epidermis
46
where are most obvious skin markings and why
thick skin
- dermal papillae are prominent and arrange into dermal ridges
- the epidermis then indents to produce epidermal ridges
47
what causes tension lines in the skin
gaps between collagen bundles in the reticular layer
48
where are tension li
run in a circular pattern in the neck and trunk and longitudinally in the head and limbs
49
explain incisions and tension lines
- incisions made along tension lines heal faster w less scarring
- incisions made perpendicular to tension lines heal mmore slowly and tend to scar
50
what are wrinkles
- Result from age-related decreases in collagen and elastic fibers, proteoglycans, and adipose tissue in the dermis
- Exposure to U V radiation and cigarette smoking accelerate formation of wrinkles
51
what is botox
contains a bacterial toxin that paralyzes facial muscles for 4-6 months, causing the overlying skin to appear smoother
52
how to diminish appearance of wrinkles
- botox
- fillers
- peels
- topical creams
52
what are fillers
containing adipose tissue, collagen, and/or
proteoglycans are injected into wrinkles to temporarily “fill”
them
53
what are peels
lasers, chemicals, or abrasion to remove the epidermis and superficial dermis to cause formation of new, hopefully firmer, skin
54
what are topical creams
contain ingredients that claim to reduce the appearance of wrinkles; however, most creams, particularly nonprescription products, have little effect on wrinkles
55
where is melanin produced
in vesicles called Melanosomes, in
melanocytes
56
what is melanin made of
The enzyme Tyrosinase joins 2 molecules of the amino acid tyrosine to form melanin
57
what is the purpose of melanin
to sheild dna from uv radiation
58
immediate effects of exposure to uv radiation
- melanin synthesis increases
- oxidizes the melanin, darkens
59
seondary effects of exposure to uv radiation
Damage DN A of melanocytes,
which increases melanin production
60
melanin has an effect on a vitamin. which vitamin and what does melanin do to it
vitamin d. melanin decreases the amount made. hence why people in africa have darker skin/ more melanin, preventing excess vitamin d production and opposite w people in northern europe
61
what is a freckle
Small area of increased melanin production
in a local spot
62
what is a mole (nevus)
Area of increased pigmentation,
caused by local proliferation of melanocytes
63
what is albinism
Melanocytes fail to manufacture
tyrosinase; Results in lack of skin pigmentation and
greatly increased the risk of keratinocyte DN A damage
from U V radiation
64
hair aka
pili
65
what is hair
Small, filamentous structures that project from
all surfaces of the skin except the regions with thick skin, the
lips, and parts of the genitalia
66
what kind of cells is hair made of
Consists of squamous keratinized epithelial cells
67
functions of hair
- protection
- sensation
68
hair - protection
For example, hair around the eyes and in the nose
keep out foreign objects and hair on the head protects
against U V radiation
69
hair - sensation
Sensory neurons associated with hair detect
environmental changes
70
structure of the hair
- hair shaft
- hair root
71
regions of hair shaft
- inner medulla
- middle cortex
- outer cuticle
72
what is the inner medulla
Present in thick hairs only; Includes soft
keratin in the core, similar to that in the epidermis
73
what is the middle cortex
Several layers of keratinocytes with hard
keratin
74
what is the outer cuticle
Single layer of keratinocytes with hard
keratin; Wears over time producing “split ends”
75
what is the hair shaft
Projects from the skin’s surface
– Columns of dead keratinized epithelial cells
– Each strand has 3 regions
76
what is the hair root
Portion embedded in the dermis
77
what are arrector pili muscles
attach to the dermal root sheath and contract causing Piloerection, which causes “goosebumps”
78
what is the hair bulb
Enlarged area at the base of the root with
a projection called the Hair Papilla, which supplies
capillaries to the root
79
what is average hair growth
Hair grows at different rates for different
individuals, but averages about 1-1.5 cm per month
80
what is alopecia
Baldness caused by the death of hair follicles
81
what is lanugo
Nonpigmented hair that covers the body in a
fetus; Falls out after birth
82
what is terminal hair
Thick, coarser, and pigmented hair found on the
scalp and around the eyes
83
what is vellus hair
- peach fuzz
- Thin, nonpigmented hair found on the
rest of the body; After puberty, much of the vellus hair is replaced by terminal hair but the amount differs by sex
84
how is hair color determined
Determined primarily by the amount of
melanin produced by melanocytes
85
red hair contains
pheomelanin - reddish melanin
86
why does hair turn gray or white as we age
Determined primarily by the amount of
melanin produced by melanocytes
87
what are nails made of
Consist of stratified squamous epithelium and hard keratin
88
what are the parts of a nail
- nail plate
- nail bed
89
what is a nail bed made of
- nail body
- nail root
- nail matrix
90
what is the nail plate
Portion of the nail that sits on top of the epidermal nail bed
91
what is the nail body
Visible portion of the nail plate
92
what is the nail root
Portion of the nail plate under the skin
93
what is the nail matrix
actively dividing cells
94
nail growth
Growth is continuous with fingernails growing
about 0.5 mm per week, while toenails grow more slowly
95
nail pigment
Nails contain no melanocytes, so they are translucent with an opaque half-moon shaped region near the proximal nail fold called the Lunula, which has accumulated more keratin
96
nail bed pigment
Nail beds are pinkish is a well-oxygenated individual and bluish (cyanotic) in a poorly-oxygenated individual
97
sweat glands aka
sudoriferous glands
98
what is merocrine secretion
All 4 types of sweat glands release their various products by exocytosis, this type of secretion
99
types of sweat glands
- eccrine sweat glands
- apocrine sweat glands
- ceruminous glands
- mammary glands
100
eccrine sweat glands
—Most prevalent sweat gland
– Sweat exits through a duct with a sweat pore in the epidermis
– Eccrine sweat is 99% water with small amounts of electrolytes and waste products
– Primary function is thermoregulation
101
apocrine sweat glands
—Large glands in the dermis, but found only in the axillae (armpits), anal area, and areolae (darkened area around the nipples)
– Sweat exits onto a hair follicle rather than through a pore
– Apocrine sweat is thick and rich in proteins
– When secreted, the sweat is odorless, but when metabolized by bacteria, it produces odor
– Secretion begins at puberty with influence from sex hormones
102
what is cerumen
ear wax
103
ceruminous glands
—Modified apocrine glands that secrete thick Cerumen (ear wax)
– Secreted onto hair follicles to protect and lubricate the tympanic membrane, or eardrum, of the ear
104
mammary glands
—Highly specialized sweat glands that
produce a modified sweat called milk
– Milk contains proteins, lipids, sugars, and other
substances to nourish a newborn infant
105
what are sebaceuous glands
—Branched glands with clusters of secretory cells call Acini that surround small ducts that usually empty onto a hair follicle
* Numerous in face and scalp
* Produce Sebum, a waxy, oily lipid mixture
* Secretion increases at puberty with influence from sex hormones, particularly testosterone
106
acne aka
acne vulgaris
107
acne
* Caused by an accumulation of sebum and dead cells
within the sebaceous glands producing a Comedone, or Blackhead
* If these become infected with the bacterium Propionibacterium acnes, inflammation and formation of a Pustule, or Pimple may occur and may lead to scars
* Male sex hormones contribute strongly to the development of acne and is more pronounced in males entering puberty
108
what is a comedone
a blackhead
109
what is a pustule
a pimple
110
what is a wound
—Common skin pathology defined as any disruption in the skin’s integrity
* Wounds may involve the epidermis, the dermis, and occasionally deeper tissues
111
types of skin wounds
- laceration
- burn
- cancer
111
what are burns
Skin wound caused by agents such as heat,
extreme cold, electricity, chemicals, and radiation
- Grouped based on extent and depth of tissue damage
112
first degree burns
—Superficial burns
– Only epidermis is damaged
– Erythema and minor pain are present but no blisters or
permanent damage occur
– No treatment is usually required
113
second degree burns
Partial thickness burns
Epidermis and part of the dermis are damaged
Significant pain, blistering, and possibly scarring occur
Treatment is usually required
113
third degree burns
—Full thickness burns
– Epidermis, dermis, hypodermis, and possibly deeper
tissues are damaged
– Not painful initially because of nerve damage, but
major tissue damage and significant scarring occur
– Problems with dehydration due to massive fluid loss
and infection are serious complications
– Treatment may require extensive skin grafting, which
involves transplanting skin from another part of the
body onto the wound
113
rule of nines
– Divides the body into 11 areas, each representing 9%
of the total body surface area (genital area is 1%)
– For example, a burn involving the entire right lower
limb covers 18% of the body
– Used to estimate how much fluid to give burn patients
– Must be modified if body proportions are different (i.e.
infants or obese individuals)
113
what is cancer
- ne of the most common diseases in the world
that claims millions of lives each year
* Mutations in a cell’s DN A induce the cell to lose control
over the cell cycle resulting in a Tumor, or cluster of
undifferentiated cells
* Cancerous tumors prevent the tissue from functioning
normally, and can Metastasize, or spread to other tissues
113
what does it mean if cancer metastasizes
spreads to other tissues
