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Man dropped frozen turkey in boiling hot oil and it “exploded” oil all…

- - - - layers
        
        papillary dermis: areolar connective tissue
        
        dermal papillae: superficial region of dermis
        
        projections contain capillary loops, free nerve endings and Meissner's corpuscles
        
        in thick skin, area shows up as fingerprints called friction ridges
        
        send fingerlike projections up into the epidermis
        
        superficial layer, loose fibers allow phagocytes to patrol for microorganisms
        
        reticular dermis: dense irregular connective tissue
        
        larger blood supply
        
        panacean corpuscles deep deep feel pressure
        
        about 80% of dermal thickness
        
        extracellular matrix contains pockets of adipose cells
        
        consists of collagen and elastin fibers
        
        ability to recoil
        
        bind water, keeping skin hydrated
        
        provide strength and resiliency
        
        cleavage lines are caused by many collagen fibers running parallel to skin surface
      - cells and tissues
        
        contains nerves , blood vessels and lymphatic vessels
        
        contains epidermal hair follicles, oil glands and sweat glands
        
        fibers in matrix bind the body together
        
        cells include fibroblasts, macrophages, mast cells and white blood cells
      - lines of cleavage
        
        growth lines of the dermis
        
        collagen and elastic fibers oriented in parallel bundles to skin surface
        
        externally invisible
        
        bundles function to resist stress
        
        important to surgeons because incisions parallel to cleavage line heal more readily
    - - subcutaneous layer deep to skin
      - consists mostly of adipose tissue with some areolar connective tissue
      - also called superficial fascia
      - not part of the skin but shares some of the skin's protectives functions
    - - layers from superficial to deep
        
        stratum granulosum: granular layer
        
        cells flatten, nuclei and organelles disintegrate
        
        keratinization begins
        
        cells accumulate keratohyaline granules that help form keratin fibers in upper layers
        
        4-6 cells thick, cells are flattened and the layer is thin
        
        cells accumulate lamellar granules that slow water loss
        
        cells are too far from dermal capillaries to survive , they die
        
        stratum spinosum: pricky layer
        
        keratinocytes in it appear spiked due to the fixative in tissue preparation
        
        melanosomes and dendritic cells are abundant and scattered among keratinocytes
        
        several cell layers thick
        
        stratum lucid: clear layer
        
        consists of thin, translucent band of 2-3 rows of clear, flat, dead keratinocytes
        
        filled with eleiden and oily protein
        
        found only in thick skin (palms of hands and soles of feet)
        
        lies superficial to the stratum granulosum
        
        stratum basale attached firmly to dermis
        
        melanocytes are found in this layer
        
        1 daughter cell takes 25-45 days to reach surface from basal layer, and other daughter cell remains in stratum basale as stem cell
        
        deepest single layer of stem cells
        
        stratum corneum: horny layer
        
        accounts for 3/4 of epidermal thickness
        
        cells are dead and still function for protection, prevention of water loss, barrier
        
        20-30 rows of flat, enucleated, keratinized dead cells
        
        cells change by going through apoptosis and slough off as dandruff and dander
      - cells types
        
        melanocytes
        
        melanosomes exocytosis into keratinocytes where they protect from UV damage
        
        produce pigment melanin which is packaged into melanosomes
        
        located in deepest layer of epidermis
        
        dendritic (Langerhans) cells arise from bone marrow and migrate to the epidermis
        
        macrophages that patrol deep epidermis
        
        keratinocytes arise in stratum basle
        
        highly connected by desmosomes and tight junctions
        
        millions slough off everyday
        
        produce keratin that gives the skin its protective properties
        
        tactile epithelial (Merkel) cells present in epidermal-dermal junction
        
        found in the stratum basale
        
        associated with free nerve ending in the dermis
        
        associated with dislike sensory nerve ending
      - epidermal derivatives
        
        nails
        
        scale-like modification of epidermis that contain hard keratin
        
        act as protective cover for distal, dorsal surface of fingers and toes
        
        consist of free edge, nail plate and root
        
        nail bed is epidermis underneath keratinized nail plate
        
        nail matrix: thickened portion of bed responsible for nail growth
        
        sweat glands: sudorifeous glands
        
        eccrine sweat glands
        
        ducts empty into pores, secretion is sweat
        
        function in thermoregulation
        
        abundant on palms, soles , forehead
        
        apocrine sweat glands: begin functioning at puberty
        
        confined to axillary and anogenital areas
        
        merocrine secretion function
        
        empty into hair follicles, secretion is viscous milky/ yellowish sweat that contain fatty substances and proteins
        
        bacteria break down sweat, leading to body odor
        
        modified apocrine glands
        
        ceruminous gland
        
        lining of external lear canal, secrete cerumen -earwax
        
        mammary glands
        
        secrete milk
        
        hair
        
        consist of flexible strands of dead keratinized cells
        
        warn of insects on skin, guards against physical trauma
        
        protect from heat loss, shield skin from sunlight
        
        produced by hair follicles and contain hard keratin
        
        sebaceous (oil) glands
        
        relatively inactive until puberty: stimulated by hormones-androgens
        
        secrete sebum
        
        develop from hair follicles and secrete into hair follicles
        
        widely distributed except for thick skin of palms and soles
  - - - cutaneous sensations: part of nervous system
        
        free nerve endings sense painful stimuli
        
        exteroceptors respond to stimuli outside body like temperature and touch
      - metabolic functions
        
        vitamin D synthesis
        
        keratinocytes' chemicals disarm some carcinogens
        
        collagenase synthesis that aids in natural turnover of collagen
        
        activate some steroid hormones
      - body temperature regulation
        
        if body temperature rises, sensible perspiration to cool body: dilation of dermal vessels can increase sweat gland activity to produce 12 l of noticeable sweat
        
        under normal resting body temperature, insensible perspiration : 500ml of unnoticeable sweat
        
        cold external environment
        
        dermal blood vessels constrict
        
        skin temperature drops to slow passive heat loss
      - blood reservoir
        
        skin holds about 5% of body's blood volume
        
        skin will constrict its supply if other organs are in need
      - Protection:skin is a barrier
        
        physical barrier
        
        flat, dead, keratinized cells of stratum corneum surrounded by glycolipids, block most water and water-solubles substances
        
        some chemicals have limited penetration of the skin
        
        organic solvents- acetone, paint thinner
        
        salts of heavy metal- lead, mercury
        
        plant oleoresins - poison ivy
        
        some drugs- nitroglycerin
        
        lipid-soluble substances
        
        drug agents- enhancers that help carry other drugs across skin
        
        biological barrier
        
        epidermis contains phagocytic cells - dendritic cells
        
        dermis contains macrophages
        
        chemical barrier
        
        acid mantle: low pH of skin retards bacterial multiplication
        
        melanin provides a chemical barrier against UV radiation damage
        
        skin secretes many chemicals
        
        sebum and defensins kill bacteria
        
        cells secrete antimicrobial defensin
        
        sweat contains antimicrobial proteins
      - excretion of wastes: minimal
        
        limited amounts of nitrogen-containing wastes in sweat
    - - acts as energy reservoir
      - provides thermal insulation
      - pads and protects the body
      - drugs often injected here
  - - - skin temperature drops to slow passive heat loss
      - Vasoconstriction: The blood vessels under the skin become narrower. This decreases blood flow to skin, retaining heat near the warm inner body.
    - - Sweating: sweat glands release sweat, which cool the skin as it evaporates. This helps lower internal temperature.
      - Vasodilatation: The blood vessels under the skin get wider. This increases blood flow to the skin where it is cooler — away from warm inner body. This lets body release heat through heat radiation.
  - - - set of guidelines used to determine the percentage of the amount of skin burned on the body depending on the region. (This helps doctor's determine how critical it is and how much fluid is required.)
        
        body is broken into 11 sections with each section representing 9% of body surface, genitals account for 1%
        
        used to estimate volume of fluid loss
        
        anterior and posterior head+neck 9%, anterior and posterior upper limbs 18%; anterior and posterior trunk 36%; perineum 1%; anterior and posterior lower limbs 36%
    - - third-degree
        
        full-thickness burns
        
        skin color turns gray-white, cherry red or blackened
        
        entire thickness of skin involved
        
        no edema is seen and area is not painful, nerve endings are destroyed
      - treatment
        
        first line of treatment IV fluid; debridement of burned skin; antibiotics, temporary covering, skin graft
      - second-degree
        
        epidermal and upper dermal damage
        
        blisters appear
        
        partial-thickness burn
      - first-degree
        
        epidermal damage only
        
        localized redness, edema, pain
        
        inflammation brings healing cells to the area
        
        partial-thickness burns
    - - over 10% of the body has third-degree burns
      - there are third-degree burns of the face, hands or feet
      - over 25% of the body has second-degree burns
- - - - severe pain
      - redness
      - blisters
        
        infection
        
        scarring
  - - - dehydration and electrolyte imbalance
        
        renal failure
        
        circulatory shock
        
        loss of ability to maintain body temperature
  - - - pain
      - redness