1 / 56

Chapter 4

Chapter 4. Skin and Body Membranes. BODY MEMBRANES. _________________________cover surfaces,line body cavities and forms protective-sometimes lubricating –sheets around organs. I.Classification of Body Membranes. A) EPITHELIAL MEMBRANES Covering and lining membranes

nuala
Download Presentation

Chapter 4

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chapter 4 Skin and Body Membranes

  2. BODY MEMBRANES • _________________________cover surfaces,line body cavities and forms protective-sometimes lubricating –sheets around organs

  3. I.Classification of Body Membranes • A) EPITHELIAL MEMBRANES • Covering and lining membranes • All have an underlying sheet of connective tissue

  4. 1) Cutaneous Membranes= skin • Superficial epidermis is____________________________________ • Underlying dermis is dense(fibrous) connective tissue.The superficial tissue is exposed to air and is a ________________________________ Composed of keratinizing stratified squamous epithelial Dry membrane

  5. 2) Mucous Membranes-made of varying types of epithelial tissue resting on a loose connective tissue called ____________________ and lines all membranes that open to the exterior(hallow organs of respiratory tract,digestive,urinary and reproductive… • Mucosa refers to location,not cellular makeup….But most mucosa are stratified squamous (mouth and esophagus) epithelium or simple columnar (rest of digestive tract)----all wet and bathed in secretions) Lamina propria

  6. 3)Serous membranes(serosa)- • Has a layer of simple squamous epithelium on a thin layer of ________________________________ • Serosa are closed to the exterior (except for dorsal body cavities and joint cavities) Areolar connective tissue

  7. Occur in pairs…The __________________lines a specific portion of the ventral body cavity • Parietal layer folds in itself to form ________________-covers outside of the organs in that cavity • Serous layers separated by___________________-secreted by both membranes Serous fluid Parietal layer Visceral layer

  8. Serous fluid allows organs to slide against ea. Other and cavity w/o friction

  9. SEROUS NAMES RELATED TO LOCATION peritoneum • ______________________covers abdominal cavity • ____________________-surrounds lungs • _______________________surrounds heart pleural pericardium

  10. Connective Tissue membranes • Composed of ______________________and has NO epithelial cells-line capsules surrounding joints • Line small sacs of connective tissue called bursae and the tubelike tendon sheath----all cushioning organs against each other and tendon across bone Soft areolar connective tissue

  11. II.The Integumentary Sysyem(skin)-cutaneous membrane • The Integumentary Sysyem(skin)-cutaneous membrane • functions –most importantly protective….against mechanical damage,chemical damage, • bacterial damage, • UV effects,thermal effects and dessication(drying out) • ---also aids in controlling body heat • ---aids in excretion of urea and uric acid • ----synthesizes Vitamin D

  12. The uppermost layer is full of _____________-and is cornified or hardened-help prevent water loss • Capillaries and sweat glands work on thermal control • ____________sense touch,pressure,temperature and pain keratin Cutaneous sensory receptors

  13. Structure of skin • Epidermis-stratified squamous epithelial capable of keratinizing(hardening) • _________-underneath-mostly dense connective tissue • Epidermis and dermis strongly connected,but some abuse can cause them to separate—interstitial fluid comes between layers making a _____________ • _____________is below dermis and mostly adipose----not actually considered part of skin,but attaches skin to organs beneath---works as “shock absorber” and insulates from extreme temperatures Subcutaneous tissue dermis blister

  14. 1)Epidermis- strata • has 5 layers or _______________.From inside out they are stratum basale,spinosum,granulosum,lucidum and corneum • avascular • most cells are ______________________________which make keratin keratinocytes

  15. Stratum basale-closest to dermis and connected along a wavy borderline.Contains epidermal cells that that get the most nourishment by diffusion from dermis;constant cell division-MILLIONS OF NEW CELLS DAILY(also called stratum germanitivum),daughter cells pushed upward • Stratum Spinosum and stratum granulosum become flatter and increasingly full of keratin

  16. When the previous cells die,they form the clear _________________________________-not in all skin regions-only where skin is hairless and extra thick-ie.palms and soles;it secretes a water repellent glycolipid into extracellular space;distant from blood supply,so little nutrients-doomed cells Stratum lucidum

  17. OUTERMOST Stratum corneum—20-30 cells layers thick and is ¾ of epidermal thickness;cornified,shinglelike dad cells,filled w/ keratin;protects lower cells;dandruff sloughs off from here • We have a totally new epidermis every 25-45 days • ___________________pigment that ranges in color from yellow to brown to black produced by melanocytes(in stratum basale).When skin is exposed to sun,this stimulates these cells tomake more of the pigment---THUS tanning melanin

  18. Melanin accumulates in membrane bound granules called __________________.They move to the end of the melanocytes and taken up by keratinocytes .THERE,melanin froms a pigment umbrella over superficial side of nuclei-shielding DNA from UV • _______________and moles are where melanin are concentrated in one spot melanosomes freckles

  19. 2)dermis-‘hide Dermal papillae Papillary layer • strong,stretchy • dense fibrous connective tissue • ___________________upper dermal region;______________-peglike projections from superior surface-many containing capillary loops-thus nutrients;some have pain receptors-___________________ or touch receptors-_________________________________ Free-nerve endings Meissner’s corpuscles

  20. Has whorled rings on soles and palms,increasing friction and gripping ability----genetically determined…..sweat pores provide for fingerprints

  21. Reticular layer • 2)_______________________________deepest skin layer w/blood vessels,sweat and oil glands and _______________________________deep pressure receptors;phagocytes act here at reticular layer • Collagen and elastic fibers found in dermis.collagen gives toughness and attract water for hydration.Elasisic fibers give elasticity that declines w/age • Many blood vessels help w/ body temp.homeostasis.skin is red when hot due to engorging of blood Pacinian corpuscles

  22. ___________________________________ happen in bedridden patients not turned regularily-pressure restricts blood supply and redness when pressure is released • Rich nerve supply Debicutus ulcers

  23. C-Skin Color-3 pigments: • 1-melanin in epidermis • 2-carotene in stratum corneum and subcutaneous tissue • 3-O2-rich hemoglobin in dermis • ----varying amounts of thr above create the numerous skin colors.Which is showing up more in Caucasians?_________________________ • ________________________hemoglobin is poorly oxygenated---can happen during heart failure and severe bleeding hemoglobin cyanosis

  24. What else affects skin color?: • Emotions and various disease states: • ___________________-redness-blushing,hypertension,inflammation,allergy • ___________________-blanching-pale—fear,anger also anemia,low blood pressure,impaired blood flow • ___________________-yellowness-liver disorder • ____________-sites wher blood has escaped and clotted in tissue spaces;can happen w/disese or vitamin C deficiency • _________________-clotted blood mass jaundice pallor erythema hematomas bruises

  25. D.Appendages of the Skin Cutaneous glands • 1-__________________________________-exocrine glands-release secretions to skin’s surface via ducts • a)Sebaceous glands-oil glands-excepts on palms and soles—some open into hair follicle and some to surface • ________________-is product-clump of oil and cells;keeps skin moist and prevents hair from drying out sebum

  26. ______________(sudoriferous glands)-many in the skin-2 types: 1)eccrine glands-all over body and make sweat(mostly water,NaCl,vitamin C and tarces of metabolic wastes(ammonia, urea,uric acid and lactic acid.It is acidic and inhibits bacteria….sweat comes through a poer(not same as facial pores);helps regulate temp.(37 C Sweat glands

  27. Apocrine glands • 2)_____________________________-mostly at axillary and genital areas;ducts empty into hair follicles;contains fatty acids and proteins—giving milky/yellowish color.It is odorless,but that changes whe bacteria use it as food:function at onset of puberty regulated by androgens(male sex hormones)----have been connected to sexual foreplay

  28. 3-Hair and Hair Follicles • . • 1)Hairs made by hair follicles and is flexible epithelial structure;root in ________________and shaft protrudes It is formed by mitosis of stratum basale epithelial cells in matrix(growth zone)-become keratinized and die as pushed forward---mostly hair contains protein • Hair has central core called a medulla surrounded by a cortex.This is covered by a cuticle(most keratinized region)-gives strength • Hair pigments made by melanocytes in hair bulb Hair follice

  29. Variety of shapes and sizes(eyebrows v. head then skin hair).If shaft is flat and ribbonlike-hair curly or kinky.If shaft is round-straight or coarse hair • Hair all over except soles,palms,nipples and lips • Fastest growing tissue in body • Have hormonal control

  30. 2) hair follicles-contain inner epidermal sheath that forms hair/outer dermal sheath is connective tissue/papilla yield blood supply to matrix in hair bulb • ______________________________smooth muscle that raise hair in response to temp Errector pilli

  31. Free edge Nail matrix • 3) Nails-scalelike product of dermis(corresponds to hoof or nail) • Each nail has a _______________,a body(visible and a root(imbedded in skin) • Nail bed in stratum basale and inner ____________________,responsible for growth-cells become keratinized and die • Part appears pink due to vascularization in dermis • ___________________ appears white lunula

  32. E.Homeostatic imbalances of skin • 1) Infections and Allergies • ___________________________-fungal,itchy red ,peeling skin(tinea pedis) • Boils and Carbuncles-inflammation of hair follicles and sebaceous glands—often dorsal neck.Carbuncles are caused by bacteria-esp. Staphylococcus aureus Athlete’s foot

  33. _____________________-small fluid filled(fever blisters)-itch and sting –caused by a herpes simplex virus-can be activated from dormancy from emotions,fever,UV light-usually around lips or oral mucosa • _____________________________-itchy,red,swelling and turns into blisters-exposure to chemicals like poison ivy Cold sores Contact dermatitis

  34. ___________________-pink,water-filled raised lesions around nose and mouth;w/yellow crust;caused by Staphylococcus • _____________________-chronic overproduction of cells w/ red epidermal lesions—probably autoimmune impetigo psoriasis

  35. 2-burns-tissue damage and cell death caused intense heat,electricity,UV light or certain chemicals---This can have a domino effect on several organ systems • destroys cells • Life threatening from 1) loss of fluids as they seep from burned surface-dehydrating and fluid imbalance-could shut down kidneys and cause circulatory shock

  36. ___________________________-divides body into 11 areas,ea. 9% of total body surface area+ area around genitals-determines % burned • 2) infection later is a leading cause of death-after 24 hrs.,pathogens invade the area and multiply quickly RULE OF NINES

  37. Classification: • 1st degree-only epidermis is damaged-red and swollen • 2nd degree injury to epidermis and upper dermis-regrowth will occur • 1st and 2nd degree are ___________________________burns • 3rd degree-destroys entire thickness of skin(full-thickness burns) Partial-thickness burns

  38. Critical if a) over 25% covered w/ 2nd degree b) over 10% 3rd degree OR c) 3rd on face ,hands or feet

  39. 3-Skin Cancer • Most neoplasms benign(ex-wart) • Affect 1/5 americans • _________________________________-least malignant and most common-affects stratum basal so cannot form keratin;boundary between epidermis and dermis lost;fairly slow growing • _______________________________-from stratum spinosum-scalp,ears,hands-grows rapidly,but if caught early,prognosis is good Squamous cell carcinoma Basal cell carcinoma

More Related