Integumentary System (Your Skin) Flashcards
What does the integumentary system include?
Skin Hair Oil and sweat glands Nails Sense receptors (touch, hot/cold)
Subcutaneous layer
Lies under skin layers
Areolar and adipose tissue
Storage depot
Skin layers
Epidermis (top layer)
Superficial layer
Epithelial tissue
Dermis (underneath)
Mainly connective tissue with elastic fibers
3 pigments make up skin color
What 4 cell types does the epidermis contain?
Keratinocytes
Melanocytes
Langerhan cells
Merkel cells
Epidermal layers? Thick vs thin
Mostly thin skin - 4 layers on body
Thick skin - 5 layers (palms and soles of feet)
What are the 5 layers from deepest to superficial?
Stratum basale (how cells are made, bottom) Spinosum Granulosum Lucidium (only in thick) Corneum (top layer)
What happens during keratinization ?
New cells made in the stratum basale layer
Cells move up from one epidermal layer to the next.
Definition- Accumulate more keratin as they move to top of skin
Dead cells slough (fall) off
Takes about 4 wks from stratum basale to rise to surface
- excessive amount shed from scalp is DANDRUFF
What’s dandruff
Excessive amount of dead keratin cells shed from the scalp (part of keratinization process)
What does the dermis layer include?
- type of tissue?
- what does it have?
Dense irregular connective tissue
-collagen and elastic fibers
Divided into 2 regions
-papillary: more superficial
-reticular: deeperWhat is in the papillary region ? (In the dermis)
(Superficial)
-areolar tissue with elastic fibers
DERMAL PAPILLAE: finger-like projections that project into epidermis
- finger print region
- contain blood capillaries
-nerve endings (sensory receptors)What are the nerve endings in the dermal papillae in the papillary region in the dermis region? (2)
Meissner corpuscles- touch
Free nerve endings- warmth, pain, coolness, tickling, itching
What does the reticular region include in the dermis region?
- tissue?
- has?
(Deeper)
-attached to subcutaneous layer
-dense irregular connective tissue w/ collagen and elastic fibers
Provides:
-skin strength
-extensibility
-elasticity
Hair follicles, nerves, oil glands, sweat glandsWhat 3 pigments produce skin color?
Melanin
Hemoglobin
Carotene
What in the cell causes cancer?
When the nucleus mutates (why when melanocytes are produced, then protect the nucleus)
Melanin distribution can result in albinism
What is albinism
Inherited trait where no melanin is produced
Melanin distribution can result in freckles
What are freckles?
Melanin accumulates in patches
Melanin distribution can result in age spots
What are age spots?
Melanin accumulation with age & forms flat blemishes
Melanin distribution can result in Nevus (mole)
What is nevus
Localized overgrowth of melanocytes
-round, flat, or raised areas
Melanin distribution can result in vitiligo
What is vitiligo?
Condition where melanocytes are partially or completely lost from areas of skin
-irregular white areas on skin
What is hemoglobin?
O2 carrying pigment molecules in red blood cells (why we blush!)
In light skin, plays larger role in reddish hue of skin
-oxygen content in epidermal capillaries
What’s carotene?
Yellow-orange pigment
Precursor of Vitamin A
Accumulates in stratum corneum (top layer of skin) and fatty dermis areas
What is melanin?
Amount and shades produce all skin colors
-pale yellow to black
Absorbs UV light for protection
Melanocytes (produce melanin) in stratum basale and mucous membranes in body
All races have equal # of melanocytes
Difference in color is amount of melanin produced (ancestors location determine melanin production, evolutionary history!)
Skin/ integumentary system is also known as?
Cutaneous membrane
Hair
- what is it?
- location?
- description?
- types?
Columns of dead, keratinized epidermal cells
Not on soles of feet or palms
Hair thickness and pattern determined by genetics and hormones (it’s hereditary, gray early)
Body hair, scalp hair, eyebrows/eyelashes
Body hair
Sense light touch
Scalp hair
Protects from UV light and decreases heat loss
-lose about 70-100 scalp hairs per day
Eyebrows/eyelashes
Protect eyes from particles
What glands do we have?
Sebaceous (oil) glands
Sweat glands
Ceruminous glands
Sebaceous glands
What are they?
Location?
Function?
Oils glands
Connected to hair follicles
Secrete sebum
-lipids and cell debris (dead skin & hair cells)
Function:
-softens skin, waterproofing surface
- blackheads
- pimples and boilsBlackheads
Enlarged sebaceous glands with accumulated sebum
Pimples and boils
Bacteria metabolizing sebum
Sweat glands
What are they?
Location? Function?
Sudoriferous glands
3-4 million per person
Deep dermis, subcutaneous layers
Release sweat into hair follicles or on skin surface through pores
Two main types:
Eccrine & Apocrine sweat glandsEccrine sweat gland characteristics
Most common sweat gland
Located throughout body regions
Produce watery sweat that regulates body temp.
Apocrine sweat gland characteristics
Limited to axillary (armpit) and public regions
Produces thicker sweat; often released during emotional stress
Water w/ electrolytes & metabolic waste
(Release into hair follicles!)
Ceruminous glands
Earwax glands
In ear canal & outer ear
Secrete cerumen
-lipids and cell debris
-prohibits entry of debris from entering eat canalNails
What are they?
Function?
Plates of hard, tightly packed dead keratinized epithelial cells of epidermis
Function: -protect ends of fingers & toes
- Aids in grasping objects
Accessory structure of the integumentary system include?
Hair nails and glands
Pathology of the skin includes
Acne, burns, and skin cancer
Acne
How is it caused?
What is it actually called?
Acne vulgaris- affects 96% of adolescents & young adults to some degree
Cause- accumulation of sebum and dead cells within sebaceous glands
-occasionally infected with bacteria resulting in inflammation & formation of a pustule (pimple)
Male sex hormones (like TESTOSTERONE) are primary cause
Wounds
What do they include?
Definition?
Common skin pathology; defined as any disruption in skin's integrity
Includes:
-lacerations (cuts)
-burns
-skin cancersCancer
Definition?
Cause?
One of the most common diseases in the world; caused by mutations in DNA that induce a cell to lose control of cell cycle
(Cancer), unchecked cell division
Leads to?
This eventually leads to formation of a large population of undifferentiated cells known as a tumor
What are cancerous tumors about to do?
They are able to metastasize
-tumors cells spread through blood or lymphatic vessels to other tissues & continue to divide
Most, but not all cancer cells do this. SPREAD, circulated throughout the body!
How many cancers affect the skin?
What are they linked to?
3
Linked to UV radiation exposure
What are the other factors that can increase risk for developing cancer, besides UV exposure
Exposure to:
- Cancer-inducing chemicals, toxins or agents called carcinogens
- Forms of radiation
Norciceptors
free nerve endings that sense pain rapidly. other free nerve endings sense tickle, itch, and some touch
Merkel (tactic) disc
slowly sense touch near surface (skin receptor)
Meissner corpuscle
rapidly senses touch near surface (skin receptor)
Ruffini corpuscle
slowly senses stretching in deep layers of skin (skin receptor)
hair root plexus
senses movement of the hair (skin receptor)
pacinian corpuscle
senses pressure (skin receptor)
rules of nines
used for?
used to estimate the surface area affected by burns in an adult
- method for estimating how much body has been affected by a burn
- grades extent of burn
- body divided into 11 areas representing 9% of the total body area
whats a burn?
wound caused by agents such as heat, extreme cold, electricity, chemicals, and radiation
how to classify burns?
3 classes according to EXTENT & DEPTH of the tissue damage
Location of each burn?
1st- epidermis only
2nd- epidermis and part or all of the dermis
3rd- epidermis, dermis, hypodermis, and possibly deeper tissues
What does the 1st degree burn include?
characteristics, treatment, and example
- mild pain
- redness (no blisters)
- skin functions normally
- treatment: flush w/ cold water to relieve pain
- heals within 3-6 days
- example: sunburn/grasp hot iron
What does the 2nd degree burn include?
characteristics, treatment, and example
(partial thickness burns)
- pain/scarring
- redness -ex. sunburn badly to get blisters
- blisters (epidermis separates from underlying layers & fluid fills void)
- edema
- hair follicles & glands are NOT injured
- some skin function is lost
- if no infection and no grafting required, heals within 3-4 wks
What does the 3rd degree burn include?
characteristics, treatment, and example
- severe pain (burned region is numb due to nerve damage)
- not generally painful @ first bc nerves are destroyed
- marked edema -MOST damaging wound
- marble-white to black color
- most skin functions are lost
- tissue damage (major)
- susceptible to infection
- slow healing
- may require skin graft to promote healing & minimize scarring
- loss of hair follicles
hair shaft
projects above the skin surface
sebaceous gland applies to hair how?
its ATTACHED to the HAIR FOLLICLE
its why hair gets oily
hair root plexus
nerve endings surround hair follicle- sensitive to touch
Arrector pili muscle
bundle of smooth muscle attached to follicle
contraction causes hairs to stand up (“goose bumps”)
bulb
contains?
area at the base of the hair
contains blood vessels, melanocytes
contains hair matrix- responsible for hair growth
hair follicle
surrounds root portion of the hair
cuticle
fold of epidermis that hides nail root
stratum corneum of epidermis
nail root
buried in fold of skin
portion that is not visible
lunula
thick, white part of nail
white half moon
nail body
(plate) visible portion of the nail
pink due to underlying blood vessels
nail matrix
contains?
proximal portion (of the nail root)
contains dividing cells, which produce new nail cells
-keratinization takes place as nails grow outwards
-growth: 1mm/week
free edge
extends past the finger or toe
What are the 3 types of skin cancer?
basal cell carcinoma
squamous cell carcinoma
malignant melanoma
basal cell carcinoma
- most common of all cancer types
- skin is regularly exposed to UV radiation
- RARELY metastasize to other tissues
- can be resolved successfully w/ surgical removal (using liquid nitrogen)
- cancer of keratinocytes in stratum basale; generally forms a nodule w/ “cratered” center
- (its red/pink easily curable, and usually flaky)
squamous cell carcinoma
- second most common of all cancer types
- tumors more likely to metastasize than basal, surgical removal still useful
- may ulcerate & bleed
- cancer of keratinocytes in stratum spinosum (3rd layer); forms scaly plaques that bleed or ulcerate
- (usually on head & neck)
malignant melanoma
- CANCER OF MELANOCYTES
- “arms” of cancerous melanocytes extend down into dermis & access dermal blood vessels; enables cells to spread to other tissues via bloodstream
- treated w/ surgical removal & possibly radiation therapy or chemo
- prognosis depends on size of tumor, depth to which it extends into dermis
what does malgnant melanoma start out as?
moles
How can malignant melanoma be distinguished?
what does it need to be distinguished from?
can be distinguished from other skin cancers & normal moles using ABCDE rule
whats the ABCDE rule for malignant melanoma?
A: Asymmetrical shape (2 sides do NOT match)
B: Border irregularity
C: Color, usually blue-black or variety of colors
D: Diameter generally larger than 6mm (size of pencil eraser)
E: Evolving (changing) shape & size
Process used to heal a wound in the dermis vs epidermis
dermis: fibrosis
epidermis: regeneration
what are skins (mostly dermis) functions?
protects body, regulates body temp, detects cutaneous sensations
makes vitamin D, & excretes & absorbs various substances
what color are each blood vessel?
red- artery (usually thicker)
blue- vein
describe sebaceous oil glands
lie in the dermis
open into hair follicles or directly onto the skin
secrete oil sebum which….
-keeps hair from drying out
-prevents excessive water evaporation from the skin
-keeps skin soft
-inhibits growth of certain bacteria
describe eccrine sudoriferous sweat glands
found throughout the body
- secretory portion in deep dermis
- open directly to OUTSIDE through pores
- secrete watery sweat in response to rise in temp and emotions
- most common sweat gland
- remove heat by evaporation, thereby cooling the skin
describe apocrine sudoriferous sweat glands
found in axillae, groin, areolae, and beards
- secretory portion in subcutaneous layer
- open into HAIR FOLLICLE
- secrete viscous milky or yellow sweat in response to EMOTIONS
- sweat similar to eccrine but contains lipids and proteins
- sweat interacts with bacteria & produces body odor
which part of the hair is actively mitotic (growing)?
hair matrix, (which is in the bulb)
which epidermal stratum is absent in thin skin?
stratum lucidum
which parts of the skin are responsible for fingerprints?
papillary layer (this is in the dermis which includes the dermal papilla)
what comes after (deep to) the 4 or 5 layers in the epidermis?
the papillary layer of the dermis
list specific cell types and # of cell layers in each stratum
basale- keratinocytes, merkel cells, melanocytes, & langerhan cells, 1 layer
spinosum- langerhan cells, keratinocytes, 5-7 layers
granulosum- keratinocytes, 3-5 layers
lucidum- keratinocytes, 2-3 layers
corneum- dead keratinocytes, 20-30 cell layers
how does melanin aid in protection of the body?
absorbs UV light, protects skin from skin cancer
how does keratinization aid in protection of the body?
new cells are made in stratum basale and keratinization is the process/movement that moves them up from 1 epidermal layer to the next as they accumulate keratin
replenish old/dead cells
how do free nerve endings aid in protection of the body?
senses pain & temperature (hot and cold)
which layer of skin contains the most accessory organs
dermis
which layer of skin contains pacinian corpuscles
dermis
which layer of skin contains a basement membrane
epidermis (bottom layer (stratum basale) its in epithelial cells!)
which layer of skin can be subdivided in to five more layers
epidermis
You go to the beach to swim on an extremely hot sunny afternoon. Describe two ways in which your
integumentary system acts to preserve homeostasis during your outing.
sweat to maintain normal body temp & skin protects you from UV rays
- sweat cools down body (eccrine)
- melanin (melanocytes provide protection from UV)
Everyone has roughly the same number of melanocytes, however we do not have the same color skin.
Explain how this is possible
amount of melanin produced in each person by their melanocytes is different
Describe how inflammation helps a wound heal
it sets the stage, there is an increase in blood flow to the wound. more white bloods cells rush to area and attack antibodies. inflammation lets proteins and other substances seep into fluid to form a scab/clot
Fibrosis
in the dermis
blood clot forms
immune cells, fibroblasts, and epithelial cells migrate into the wound
scab forms
epithelial cells bridge wound beneath it
fibroblasts help form scar tissue
blood vessel walls grow, reseal and restore normal blood flow
regeneration
in epidermis
basal epithelial cells detach from basement membrane
they go into the wound and enlarge
adjacent basal cells slide into the wound
epidermal growth factor stimulates stem cells to divide and replace migrating cells
when the cells meet, they stop moving, grow, and build new layers completing the wound repair
You’re outside on a 100° day and you’re sweaty
which sweat gland and why?
eccrine (most common) usually sweat with this gland
Right before a blind date, your get nervous and your palms get “clammy”.
apocrine sweat gland EMOTION
Arrector pili muscles must be attached to which accessory organ?
hair follicle
Chemotherapy is designed to attack rapidly growing and dividing cells. Based on what you know about
the skin, list three locations (including in accessory organs) that would be possible targets.
epidermis, hair and nails
skin has rashes, lose hair and nails
On an outdoor picnic, an ant crawls onto your hand, causing you to flinch.
accessory organ?
meissner corpuscles and merkel (body hair)
As you are cooking dinner, you accidentally grab a hot pot handle and spill the food on the floor.
accessory organ?
free nerve endings
Before going on stage, your armpits begin to sweat.
accessory organ?
apocrine sweat gland
A long lost friend sees you for the first time in years, and greets you by giving you a hug.
accessory organ?
(skin receptors)
- meissner & merkel: touch
- pancinian corpuscles: pressure
Blackheads are caused by the clogging of pores by oily secretions.
accessory organ?
sebaceous (oil) gland
While at the beach, you forget sunscreen and get a burn bad enough to form blisters.
degree?
2nd degree
You accidentally brush a hot iron with your hand, but 10 minutes later its better.
degree?
1st
In this type of burn, like that from a fire, skin grafting is usually necessary
degree?
3rd
causes of vitiligo and how it affects the skin?
melanocytes are partially or completely lost from areas of the skin
causes irregular white areas on the skin
causes of melanoma and how it affects the skin?
caused by too much exposure to the suns UV rays
ABCDE rule
why do elderly people get colder, over heat, and have wrinkles?
colder- not as much blood flow through tissues, heat carried by blood isnt there
over heat- sweat glands dont sweat as much, body doesnt cool down
wrinkles- loose collagen & elastic fibers, reticular skin fibers too with age so their is no more plumpness/elasticity just wrinkles
why do wrinkles occur?
age, lose collagen, elastic, & reticular fibers
part of genetics, sun exposure, and make-up (stretching of skin)
Langerhan cells
Immune response for skin
Kills bacteria that might want to enter skin
Merkel cells
Least numerous
Detect touch sensations
Keratinocytes
90% of epidermal cells
Keratin- waterproofing protein
Melanocytes
Produce melanin
Skin color pigment
What kind of cells are in epidermis
Keratinized stratified squamous epithelial
