Transcript Nerve activates contraction
Integumentary System
Integumentary System
Skin Hair Nails Associated Structures (vessels, nerves, glands)
Membranes
________________ membranes – Cutaneous – Mucous – Serous Parietal vs visceral Pleura, pericardium, peritoneum
Integumentary System
Skin (cutaneous membrane) Main layers – _____________to _____ Epidermis Dermis Hypodermis – not always considered part of skin
Functions of Skin
Protection Sensation Movement without energy Excretion Vitamin ____ production – needed to absorb calcium Sun+Skin Vit D blood kidney/liver calcitriol regulates calcium & phosphorous Immunity Healing Wounds Body temperature homeostasis vasoconstriction & vasodilation blood
Epidermis
Epidermis – __________ layer _____________ stratified squamous epithelium Avascular (hardened by keratin) Renews itself ~ every _____ days
Epidermis – cell types
_____________________ produce keratin – waterproofing protein Originate in deeper layers & get pushed to surface – becomes keratin filled & dies Connected to each other by desmosomes & tight junctions Cell production & keratinization are accelerated in areas of _____________ Callus – thickened skin
Epidermis – cell types
• ___________________ • Produce melanin • Prevents DNA mutation from the UV radiation • • ______ increases melanin production Same ________in everyone, but different _______ of pigment produced • Accumulation of melanin results in freckles and moles
Epidermis – Skin Color
Determined by three factors: Types of pigments present Melanin Carotene – brown, black, or yellow pigment Orange-yellow pigment from some vegetables Vitamin A precurser – vitamin A forms retinal which is needed for sight Accumulates in adipose and stratum corneum cells Hemoglobin Red, oxygen-carrying pigment in erythrocytes More obviously detected in fair skin Blood circulation Stratum _______________ thickness
Skin as a Diagnostic
Skin color is influenced by emotional & disease states: You should know the states that cause these.
Cyanosis – _____________ color - lack of oxygen Erythema – _____________ – heat, inflammation, fever Albinism – genetically black, but white – _____melanin produced from melanocytes Pallor – paleness – lack of ________ flow Jaundice – ____________ color – liver damage; accumulation of bilirubin Bronzing – bronze (tan) – Addison’s disease Hematomas – black & blue – blood under skin
5 strata of the Epidermis – Deep to Superficial Stratum basale highly _______________(produces new skin layer) ~ 25% _____________________________ Stratum spinosum Slightly mitotic Contains Langerhan’s macrophages Several layers of many sided cells (looks ____________) Stratum granulosum Also contains Langerhans cell contains _______________________________ (helps form keratin) Stratum lucidum ONLY found in _____________ epidermis – palms, soles, callus Completely ______________________(and dead!) contains closely packed, clear cells that contain gel-like substance ________________
5 strata of the Epidermis
Stratum corneum _________________layer Also completely ________________ ________ cells Tough, waterproofing protection
Dermis
__________ layer of skin Contains hair folllicles, glands, nerves, vessels, muscle All four tissue types present Mainly strong, flexible CT - Two layers Papillary Reticular
Dermis
Papillary layer Contains Areolar CT Dermal papillae Indent into epidermis forms fingerprints Important for grip Contains blood vessel _________________ Corpuscles receptors – nerve (touch)
Dermis
Reticular layer Dense irregular CT contains blood vessels, nerves, glands, adipose _________________ Corpuscles – nerve endings responsible for sensitivity to deep pressure touch and high frequency vibration Collagen – prevents overstretching and tearing of skin ___________ – allows skin to stretch stretch marks – dermal tears
Hypodermis
Not usually considered part of the skin Also called ___________________________ layer Site of subcutaneous injections – absorbed directly into blood stream Composed mostly of _______________tissue Very vascular Functions _________ skin to underlying organs shock absorption insulation
Skin Appendages
Appendages of the Skin
Hair
Minor _______________ functions (retain heat, decrease sunburn, eyelashes protect eyes) Structure shaft – projects from skin follicle – extends into dermis root – lies within the follicle bulb – contains CT, vessels and nerves sebaceous gland – lubricates hair __________________ _________ muscle – attached to follicle and contracts to move hair (hair growth, goosebumps)
Appendages of the Skin
Hair Growth influenced by: (in this order) ______________ - main influence hormones blood flow baldness ( _______________ ) male pattern baldness - sex linked recessive genetic trait thinning – can be caused by medications, nutrition, stress, etc.
Hair Pigment caused by proportions of 3 melanin types dark hair – true melanin blonde and red – melanin with iron and sulfur gray/white hair - melanin replaced by ______ ______________ in shaft
Appendages of the Skin
Nails
Scale-like modifications of the epidermis Heavily _______________ Stratum ________ extends beneath the nail bed to form nail matrix Responsible for growth ( matrix region) Lack of pigment makes them colorless ___________ “little moon” – area of cell growth (white semicircle at base of nail) _________ – area of skin that covers base of nail
Nail Structures
Sweat Glands
_____________ glands Widely distributed in skin: abundant on palms, soles, forehead Sweat composition: mostly water with a slightly acidic 4-6 pH Function: thermoregulation • _____________glands Ducts empty into hair follicles Found mainly in anogenital & axillary region Begin to function at puberty due to hormones / pheromones Organic contents: Fatty acids and proteins – can have a yellowish color that stains clothes Odor is from associated bacteria _________________ glands Modified apocrine gland Found in outer 1/3 of ear canal Produce ear wax to trap “invaders”
Appendages of the Skin
Sebaceous glands all over except palms and soles of feet Produce _____for waterproofing Lubricant for skin & kills bacteria Most with ducts that empty into hair follicles Glands are activated at ___________: stimulated by hormones _______ – active infection of sebaceous glands
Burns
Burns
_________ denaturation and cell death caused by heat, electricity, UV radiation, or chemicals 2 main dangers ______________ –Loss of fluids & Electrolytes lead to: Renal Shutdown Circulatory shock _____________ Skin (mechanical) barrier lost Immune system depresses
Rules of Nines
Way to determine the extent of burns Primary importance is to estimate fluids needed for ______________ Body is divided into 11 areas for quick estimation Each area represents about ___%
Rule of nines diagram
Partial Thickness Burns
First-degree burns Only ____________ is damaged Local redness, swelling, & pain Usually heal in 2-3 days (short time period) with NO scarring
Partial Thickness Burns
Second degree burns Epidermis and ________ & structures within dermis are damaged Appearance of blisters of any size Skin regeneration in 3-4 weeks with some scarring There is a danger of infection
Full Thickness Burns
Third-degree burns Epidermis, Dermis, _____________ and all structures within are completely destroyed Usually _____________ at site of burn due to destruction of sense receptors Burn is gray-white, tan, brown, black, or deep cherry red Surrounded by areas of 1 st burns that will be painful & 2 nd degree Treatments are numerous but will involve skin grafting of some sort, fluid replacement and ____________________
Skin Cancer
Skin cancer is the most common type of cancer 2 out of 5 cancers are skin cancers
Skin Cancer
Cancer – uncontrolled cell growth Caused by damage to the DNA usually through chemicals or radiation Two types Benign Does not spread (encapsulated) Malignant Metastasized (moves) to other parts of the body
Skin Cancer Types
Basal cell carcinoma
_______malignant Most common type (_____% of skin cancers) Arises from stratum ____________ cannot produce keratin Boundary lost between dermis and epidermis Seldom metastasizes – treated surgically or by radiation – ____% cure rate if caught early Signs Pale marks Reddish patches Round, smooth growth with raised edge Shiny bumps Sores that don’t heal
Skin Cancer Types
Squamous cell carcinoma 2 nd most ___________ skin cancer Highest risk – fair skin, light hair, blue/green eyes Arises from stratum ___________ Metastasizes to lymph nodes if left untreated 1500-2000 deaths in US per year Early removal allows a good chance of cure Signs are same as basal cell carcinoma
Cumulative Effects
IMPORTANT TO KNOW Basal cell & squamous cell carcinomas are due to _____________ effects of the sun’s radiation (or chemical exposures as well) These tend to develop in ages 30-40s after ______of daily sun exposure
Skin Cancer Types
Malignant melanoma Least common most _________ of skin cancers Originates in ________________ Metastasizes rapidly to lymph and blood vessels Early detection is critical – see notes for survival rates
Intensive Effects
Malignant Melanoma tends to occur in younger ages (as well as older people) It is due to _______ intense exposures (aka: sunburns) This is the most serious form of skin cancer and MUST be caught early to be treated successfully!
ABCD Rule
A = Asymmetry Two sides of pigmented mole do not match B = Border irregularity Borders of mole are not smooth C = Color Different colors in pigmented area D = Diameter Spot is larger then 6 mm in diameter (pencil eraser) Mole starts growing/changing in size
Prevention
Wear sunscreen whenever outside or cover up avoid midday sun between 10-2 and beware of reflected light higher altitudes - every 1000 ft above sea level, radiation increases 4-5 % Be cautious about tanning beds Medications - tetracycline (antibiotics), Retin A, birth control, antidepressants, diuretics, and anti-inflammatories cause photosensitivity avoid sunburns
examine skin regularly - remember ABCD rule – have full body check by dermatologist once a year
Other Integumentary System disorders
Contact _______________ (Ezcema)
Exposure to allergen/irritant (ie. poison ivy) cause allergic reaction inflammation, red, itchy skin not contagious over the counter meds; sometimes Rx Prevention by avoiding allergen/irritant
Blisters
Epidermal cell injury or separation of epidermis from dermis
Warts
__________ neoplasms, but can turn malignant Contagious Remove by freezing, drying, laser therapy, chemicals
Boils
__________ infection that infects hair follicles Large, inflamed, pus-filled lesions
Tinea
_________ infections (ringworm, jock itch, athlete’s foot) Reddish discoloration, scaling, crusting Treat with antifungal agent Prevent recurrence by keeping skin dry
Impetigo
Caused by ____________ infection Mostly children Reddish discoloration turns into blisters and yellowish crusts If turns systemic, it is life threatening
Psoriasis
Cause is unknown, probably genetic Triggered by trauma, infection, stress Cutaneous inflammation, scaly lesions Due to excessive rate of epithelial cell growth
Urticaria
Hives Raised, red lesions caused by blood vessel leakage Severe itching Causes (hypersensitivity, allergic reactions, physical irritants, systemic disease)
Scleroderma
Autoimmune Affects blood vessels and CT Hard skin lesions More common in women
Decubitus ulcers
“bedsores” / pressure sores Lack of blood flow causes tissue damage
Acne
* Clogged sebaceous follicles from abnormal shedding of skin cells * Bacteria build-up in sebaceous glands * Enhanced by hormones * Over the counter meds; sometimes Rx * Prevention -avoid using oils, greasy moisturizers, facewash, and makeup -wash hands before applying makeup -use non-scented ordinary mild soap -keep hands away from face