Integumentary System Skin Appendages PDF

Integumentary System Skin Appendages AWAD MOHAMMED ALQAHTANI BSc of Anesthesia Technology King Khalid University, Muhayil Asir Organs of Integumentary System Skin Hair Nails Sebaceous glands Sweat glands  Functions of Integumentary System Covers the entir...

Integumentary System Skin Appendages AWAD MOHAMMED ALQAHTANI BSc of Anesthesia Technology King Khalid University, Muhayil Asir Organs of Integumentary System Skin Hair Nails Sebaceous glands Sweat glands  Functions of Integumentary System Covers the entire surface of the body Functions Protects against infection (Two-way protective barrier) Houses nerve receptors Secretes fluids Regulates temperature  The Skin Three layers Epidermis – thin, outer membrane layer Dermis – middle, fibrous connective tissue layer Subcutaneous layer – inner most layer of fatty tissue  Accessory Organs Located within dermis Include: Hair Nails Sweat glands Sebaceous glands Skin structure, including the three layers of the skin and the accessory organs: sweat glands, sebaceous glands, and hair  Epidermis Composed of stratified squamous epithelium Flat scale-like cells Arranged in overlapping layers called strata Has no blood supply or connective tissue Depends on deeper layers of skin for nourishment Basal layer the deepest layer  Basal Layer of Epidermis Melanocytes Cells continuously grow and push old Special cells of cells toward surface basal layer During this process Produce black Cells shrink, die, and fill with hard pigment melanin protein called keratin Gives skin color Keratinized cells allow skin to act as Protects against barrier to infection ultraviolet rays of sun Photomicrograph of the epidermis layer of the skin  Dermis Also called corium Located between epidermis and subcutaneous layer Name means “true skin” Is living tissue with very good blood supply Composed of: Connective tissue and collagen fibers Strong fibrous proteins give dermis flexible strength Houses: Hair follicles Sweat glands Sebaceous glands Blood vessels  Subcutaneous Layer Also called hypodermis Third and deepest layer Composed of fat cells called lipocytes Protects the deeper tissues of body Acts as insulation for heat and cold  Skin Appendages These appendages come from the epidermis and help maintain the body’s homeostasis. Cutaneous (relating to skin) glands Sebaceous glands Sweat glands Hair Hair follicles Nails Appendages of the Skin  Hair Hair follicle Hair root Hair shaft Arrector pili muscle Structure of a hair and its associated sebaceous gland  Nails Grow longer from nail root Cuticle Soft tissue that covers nail root Free edge Exposed edge  Sebaceous Glands Open into hair follicles Secrete the oil sebum Lubricates hair and skin Prevents drying and cracking  Sweat Glands Also called sudoriferous glands Coiled gland in dermis Sweat travels to surface in sweat duct Sweat pore – surface opening Word Building with cutane/o & derm/o sub– –ous subcutaneous pertaining to under skin epi– –al epidermal pertaining to upon skin hypo– –ic hypodermic pertaining to under skin intra– –al intradermal pertaining to within skin  Word Building with dermat/o –itis dermatitis inflammation of skin –logist dermatologist skin specialist –osis dermatosis abnormal skin condition –pathy dermatopathy skin disease –plasty dermatoplasty surgical repair of skin Word Building with melan/o & necr/o –oma melanoma black tumor –cyte melanocyte black cell  Word Building with onych/o and py/o –ectomy onychectomy surgical removal of nail –malacia onychomalacia nail softening abnormal condition of nail myc/o –osis onychomycosis fungus –phagia onychophagia nail eating (nail biting)  Word Building with –derma erythr/o erythroderma red skin ichthy/o ichthyoderma Scaly, dry skin leuk/o leukoderma white skin py/o pyoderma pus skin scler/o scleroderma hard skin xer/o xeroderma dry skin  Combining forms adip(o) fatty dermat(o) skin hidr(o) sweat, sweat glands kerat(o) horny tissue lip(o) fatty  Combining forms melan(o) black, very dark myc(o) fungus onych(o) nail pil(o) hair seb(o) sebum steat(o) fat trich(o) hair  References Quick and Easy Medical Terminology, 7th Edition, Peggy C. Leonard, Elsevier, 2014. Page Number: 310-329.