Anatomy and Physiology integumentary system Flashcards
What does the integumentary system consist of?
skin, hair, and nails
How big is the integumentary system?
10 pounds, surface area of 20 ft
skin functions (6)
1) protection from injury 2) protection from infection 3) regulates body temp 4) regulates water loss 5) chemical synthesis 6) sensory perception
three main layers of skin
1) epidermis 2) dermis 3) hypodermis (subcutaneous layer)
epidermis
- most superfical layer of skin
- covers almost entire body surface
- tenth of a milimeter thick
- 40-50 rows of stacked squamous epithelial cells
- avascular (no vessals) region
- recieves nutrients via diffusion of fluids from dermis
Keratinocytes cells
90% of epidermal cells, made of keratin (fibours protein- keeps skin waterproof/ elastic)
Melanocytes cells
8% of epidermal cells, produces melanin, contributes to skin color and absorbs UV light
Langerhans cells
arise from red bone marrow and migrate to epidermis- damaged by UV light, small portion of cells, helps immune system response
Merkel cells
least numerous of epidermal cells, deepest layer, found along tactile dics (hold cells), fuctin in sensation of touch
Stratum Corenum
nuclei and organells are destroyed by lysosomes and the cells fill keratin
Stratum lucidum
only found in the palms and soles of feet 3-5 layers of clear, flat, dead kerantinocytes, dense packed intermediate filaments, thick plasma membranes
Stratum Gradulosum
cells start to become keritanized, marks transition between deeper metabolicaly active strata and the dead cells of the superfical strata, secretes lipid rich secretion that acts as a water sealant
Stratum Spinosum
8-10 layers of kertino cytes, cells have spine like projections (bundles of filaments of the cytoskeleton) that tightly joins cells to each other, provides skin both strength and flexibility
Stratum basale
also referred to as as stratum germinatum, where new cells are formed, deepest layer of epidermis, single row of cuboidal or columnar keratinocytes
growth of epidermis
- newly formed cells in the stratum basale undergo kertinazation (gain keratin) as they are pushed to the surface and accumulate more keratin during the process
- then they undergo apoptosis or death
- evently they are slough off and replaced
- takes about 4 weeks
- rate of cell division in stratum basale increases during injury
Dermis
- deep layer pf skin under epidermis
- made of dense irregular connective tissue along with nervous tisse, blood, and blood vessels
- much thicker than epidermis
- gives skin strength and elasticity
- collogen fibers- make up 70% of dermis and give structural toughness and strength
- elastin fibers- loosly arranged in all directions to give elasticity to skin
- two distinct regions- papillary and reticular levels
Papillary layer
- superfical layer of dermis, that boarders epidermis
- contains finger like extensions called dermal papillae that protrude superficially toward the epidermis
- provide nutrients and oxygen and contain nerves and blood vessels that are projected toward the surface of the skin
- blood flowing through the papillae provide nutrients and oxygen for the cells of the epidermis
- the nerves of the papillae are used to feel touch, pain ,and temp through cells of the epidermis
Reticular Layer
- deeper layer of dermis thicker and tougher
- made of dense irregular connective tissue that contains many tough collagen and strechy elastin fibers that provide elasticity to the skin
- contains blood vessels to support the skin cells and nerve tissue to sense pressure and pain in the skin
Hypodermis
- deep under skin layer called hypodermis, subcutis, or subcutaneous tissue
- serves as flexible connection between skin and underlying muscles and bones as well as fat storage
- areolar connective tissue in hypodermis contains elastin and collagen fibers loosly arranged to strech and moe independtly of its underlying structure
- fatty adipose tissue in hypodermis stores energy in form of triglcerides also helps insulate the body by trapping heat produced by undelying muscles
- not considered to be part of skin- below dermis
- infants and elderly have less of this than adults and are therefore more sensitive to cold
Name the 3 main layers of the skin.
Name the five layers of the epidremis.
Name the 8 cell types.
Name the 2 layers of the dermis.
Skin Color
(genetic and enviormental factors)
- genetic factors- skin pigminentation
- all humans have smae # of melnaocytes
- amt of melanin produced is controlled by several genes
- lack of pigment is called albinism
- enviormental factors- exposure to sunlight
- volume of blood- hemoglobin in blood (lack of blood= skin turns blue- cynosis)
- differnece in skin color due to amt of pigment that melanocytes produce and disperse ti keraitnnocytes
Skin Glands
(2 types; with 2 subtypes)
- Sudoriferous- sweat gland
- eccrine sweat glands- secretes cooling sweat
- appocrine sweat glands- during emotional stress/ excitment
- Sebaceous- oil glands
- acne- inflammation of sebaceous gland ducts
- ceruminous- modified sweat glands of the external ear that produce earwax
Functions of hair
- on head- protects scalp from injury/ sunlight
- eyelashes and eyebrows protect eyes
- nostril and ear hair protect from foreign particles
- help in sensing light touch due to the touch receptors associated with the hair roots plexuses
functions of nails
- grasping objects
- manipulating objects
- protects end of digits from trauma
- scratching
Where is hair located? How many are there? What is there shape and how does that effect them?
- about 100,000 hairs on scalp
- about 5 million over whole body
- every part of body except- palms of hands, soles of feet, soles of fingers and toes, lips, and parts of the genitals
- diffir in size, shape, and color
- eyebrows- short and stiff, scalp- longer and flexible, rest if body- nearly invisable
- oval shaped hair shafts- produce wavy hair
- flat shaped hair shafts- produce curly/ kinky hair hair
- round shaped hair shafts- produce straight hair
Hair growth
- hair follicoles grow in repeated cycles
- three phases
- anagen- growth phase
- catagen- transtional phase
- telogen- resting phase
- each hair goes through the cycle indepdently of its neighboring hairs
Nail Anatomy
- thightly packed, hard, keratinized epidermal cells
- consists of
- nail body- portion of nail that is visible
- free edge- part that extends past the distal end of the digit
- lunula- “little moon” crescent shaped are of the nail
- hyponychium- secures nail to the fingertip
- eponychium or cuticle- narrow band of epidermis (thickened stratum corneum)
- growth of hair nails is in the nail matrix
What is each skin gland?
Hair Growth Cycle Stages
lesion
area of damaged tissuse caused by disease or trauma
cyst
thick walled, closed sac or pouch containing fluid or semisolid materials
fissure
groove or crack like sore
macule
discolored (often reddened) flat lesion
ex/ freckles, tatto marks, flat moles
papule
small (> 1cm in diameter), solid elevation in skin
polyp
mushroom-like growth extending on a stalk from the surface of mucous membranes
pustule
small elevation of the skin containing pus
ulcer
open sore or erosion of the skin or mucous membrane
vesicle
small collection of clear fluid (serum); blister
wheal
smooth, slightly elevated, edematous (swollen) area that is redder or paler than the surrounding skin
Main Causes of burns
o Careless use of small flame; i.e. Matches, cigarettes
o Hot liquid scalds
o Defective equipment; i.e. electrical equipment, cooking equipment
o Open flames esp. when flammable clothing is worn
o Unsafe use of flammable liquids
o Use of overheated water for bathing
o Improper use of chemicals, strong acids or detergents
Classification of burns
o Three main types-
• First degree
• Second degree
• Third degree
o Extent and location
• How much skin it covers and where it is
• Hospitalization for adults with 15% of body burned, 10% for child
• First degree burn
o Causes; mild sunburn, light contact with hot objects, scalding by water or steam
o Symptoms
• Redness or discoloration
• Mild swelling and pain
• Rapid healing
o Treatment
• Apply cold water
• Apply dry dressing
• Second degree burns
o Causes; deep sunburn, contact with hot liquids, flash burns from gasoline, kerosene, etc.
o Normally more painful than third degree burns because the nerve endings in the skin aren’t burned off
o Symptoms
• More depth than first degree
• Red or mottled appearance
• Development of blisters
• Swelling over several days
• Wet appearance of skin (caused by loss of plasma through damaged skin)
o Treatment
• -Apply cold (not ice) water
• Blot dry
• Apply dry sterile bandage
• Don’t use home remedies or any ointment
- Don’t break blisters
- Keep arms and legs elevated if affected
• Third degree burns
o Causes; open flame, ignited clothing, immersion in hot water, contact with hot objects or electricity
• The temperature and duration of contact are important factors in determining extent of tissue damage
o Symptoms
• Deep tissue destruction
• White or charred appearance (may resemble second degree burn at first)
• Complete loss of skin layers
o Treatment
• Don’t remove charred clothing
• Cover burns with dry sterile bandage
• Keep hands, legs, arms elevated if affected
• Keep open airway
• Don’t use ointments
• Get them to hospital as quickly as possible
• Other burns
o Chemical
• Wash off chemical and apply dressings
o Eye burns
• Flush eye with water and go to hospital
o Sunburn
• Prevention- expose skin to sun gradually to avoid burning
Athlete’s foot- what is it?
- what is it?
- fungal infection that develops in the moist areas between your toes and sometimes other parts of your foot
- also called tinea pedis- it’s the most common type of fungal infection
- contagious- spread by contact with infected person or contaminated areas like towels, floors, and shoes
Athlete’s foot symptoms
- symptoms?
- itching, stinging, and burning between your toes and on the soles of your feet
- cracking and peeling of skin
- excessive dryness on sides and soles of feet
- toenails are thick, crumbly, ragged, discolored and/or pulling away from the nail beed
Athlete’s foot causes
- causes?
- closly related to other fungal infections like ringworm and jockitch
- group of mold-like fungi called dermatophytes causes the infections which thrive in damp, close enviorments like damp socks and tight shoes taht create warm, moist areas
Impetigo basics
- highly contagious bacterial skin disease
- mostly occurs in children
Impetigo symptoms
- red sores that rupture quickly, ooze for a few days, then leave behind a golden crust
- starts around nose and mouth, but spreads to other parts of body like chicken pox
Impetigo Causes
- staphlococcus (staph)
- streptococcus (strep)
- MRSA (Methicillin Resistant Staph Aureus)- severe form of staph
Types of skin cancer
- basal cell carcinoma
- uncommon, curable if found early
- squamous cell carinoma
- occurs at skin exposed to sun
- malignat melanoma
- most common in southern hemisphere where ozone layer is thin
- deadly if not caught early
causes of skin cancer
- gentic
- exposure to ultraviolet (UV) radiation from the sun
- two types of rays
- UVA- tans, sunburns, and production of vita B
- UVB- harmful ray that causes skin cancer (also in artifical soures i.e. tanning booths ansd sunlamps)
Skin cancer prevention
- use SPF 15 min
- wear hats and long sleeves
- wear sunglasses
- avoid tanning booths
- seek shade (esp. in mid-day)
Skin cancer symptoms
- skin growth increases in size and appears pearly, translucent, tan, brown, black, or multicolored
- ABCD (asymmetry, border irregularity, differnet colors, 1/4 inch diameter)
Treatment of skin cancer
- curettage and electrodesicacation- cut of the skin cells, than treat area with electric currenr to kill the rest of the cancer and control bleeding
- convential surgery- cuts out the cancer and some healthy cells
- Mohs’ technique-shaves off one layer of skin at a time until entire tumor is removed
What are boils?
- skin infection that starts in hair follicle or oil gland
- common in face, neck, armpits, sholders, and buttocks
Boils causes
bacteria (staphlococcal bacteria) that gets in through small cuts
Boils symptoms
- hard red painful lump, 1/2 in, lump ->softer, larger, more painful ->pus pocket forms in boil
- skin around boil can become infecteed, more boils can appear, fever, lympoh nodes may become swollen
Diseases boils can cause?
- cellulities, folliculities, impetigo, stye boil, furnacle, carbuncle
- in blood stream= bacteremia
- serious infection can result from s. aureus (infection with serious side effects)
basic info about HPV
- Human papillomavirus
- STD
- DNA virus from papillomarius family
- infects keratinocytes
- over 40 types
HPV symptoms
- majority no symptoms
- some warts or cancer of the cervix, vulva, vagina, penis, and anus, RRP is a condition where warts grom in throat
at risk for HPV
- currently or at one point sexullay active (even if in monogamus realtionship)
screening for HPV
woman over and = to 30 screened for cervical cancer
none for males
pervention of HPV
- vaccines
- condoms (not 100%)
- monogamous relationship from both parties
Aging Skin
- In our 20s, the effects of aging begin to be visible in the skin.
- Stem cell activity declines: skin thin, repair difficult
- Epidermal dendritic cells decrease: reduced immune response
- Vitamin D3 production declines: calcium absorption declines and brittle bones
- Glandular activity declines: skin dries, body can overheat
- Blood supply to dermis declines: tend to feel cold
- Hair follicles die or produce thinner hair
- Dermis thins and becomes less elastic – wrinkles
Skin Markings
- friction ridges: markings on fingertips characteristic of primates - allow us to manipulate objects more easily-fingerprints are friction ridge skin impressions
- flexion lines: on flexor surfaces of digits, palms, wrists, elbows etc.- skin is tightly bound to deep fascia at these points
- freckles: flat melanized patches vary with heredity or exposure to sun
- moles: elevated patch of melanized skin, of the with hair mostly harmless, beauty marks
Skin allergies
(poison ivy, poison oak, poison sumac) Causes
- also called contact dermatitus
- caused by urushiol, oil plants, found in every part of plant
- these plants are very fragile, and stems and leaves broken by the wind and animals even the tiny holes made by chewing insects can release urushiol
- passive cause, smoke from those burned plants, when inhaled the smoke expose the skin to the chemical but also the nasal passsages, throat, and lungs, inhaled urushiol can cause a very serious allergic reaction
Skin allergies
(poison ivy, poison oak, poison sumac) symptoms
- after 1 minute skin will start to absorb urushiol though you may not feel rash right away
- after one week, rash starts to appear or it took a few hours or few days to appear
- symptoms include:
- itchy skin
- redness, red streaks
- hives
- swelling
- an outbreak of small or large blisters often forming streaks or lines
- crusting skin (after blisters burst)
- the rash is very itchy and can appear on any part of body. the rash can continue to appear on new parts of your body when
- other parts of the body touch the oil
- you spread the oil on your skin by touching other parts of your body
- you can’t give the rash to others, they must touch the actual oil
Skin allergies
(poison ivy, poison oak, poison sumac) Treatments
- wash the area with soap and water to get rid of any remaining oil on skin, the rash should go in a week or 2
- some other ways
- apply corticosteroid cream and calamine lotion to affected area
- apply wet compress every couple of hours for more than 10 minutes
- taking oral antihistamines
- oatmeal bath
- baking soda bath
Skin allergies
(poison ivy, poison oak, poison sumac) Prevention
- learn to identify the plants
- clean your clothes
- wash skin after touching plants
- use skin cream containing bentoquatam
