1. INTEGUMENTARY SYSTEM SKIN& BODY MEMBRANES

2. MEMBRANES Structure: Thin, sheet like structureStructure: Thin, sheet like structure Functions:Functions: –Cover and protect the body surface –Line the body cavities –Cover the inner surface of the hollow organs (digestive, reproductive, respiratory) –Anchor organs to each other or to bones –Cover internal organs –Secrete lubricating fluids that reduce friction during organ movements

3. Two Types of Body Membranes Epithelial MembranesEpithelial Membranes –Cutaneous membrane (skin) –Serous membranes (protection/reduce friction for organs) –Mucous membrane (line body surfaces opening directly to the exterior– such as the esophagus; mucus secretion) Connective Tissue Membrane (no epithelium)Connective Tissue Membrane (no epithelium) –Smooth & slick, secrete synovial fluid –Reduce friction b/w opposing bones, line bursa sacs

4. SEROUS MEMBRANES Two Layers:Two Layers: –Visceral: covers the surface of the organ –Parietal: lines the walls of the body cavity Thoracic Cavity=PleuraThoracic Cavity=Pleura Abdominal Cavity=PeritoneumAbdominal Cavity=Peritoneum

5. SKIN FUNCTIONSFUNCTIONS –Protection against microbes, UV rays, harmful chemicals, cuts & tears –Temperature regulations –Sense organ activity: touch, pressure, pain, temperature –Metabolic functions: synthesis of vitamin D

6. Skin: Structure Two Layers:Two Layers: –Epidermis outermost & thinnestoutermost & thinnest cells are very tightly packedcells are very tightly packed –Dermis deep & thickdeep & thick primarily connective tissueprimarily connective tissue loosely packedloosely packed Hypodermis (adipose tissue)Hypodermis (adipose tissue) –Deep to the skin/dermis –Layer of insulation

7. Epidermis Stratum CorneumStratum Corneum Stratum LucidumStratum Lucidum Stratum GranulosumStratum Granulosum Stratum SpinosumStratum Spinosum Stratum Germinativum/BasaleStratum Germinativum/Basale

8. Stratum Germinativum/Basale Contains mainy germinativum (stem) cellsContains mainy germinativum (stem) cells Cells undergoing mitosisCells undergoing mitosis Forms strong bond between epidermis & dermisForms strong bond between epidermis & dermis Merkel CellsMerkel Cells  Touch receptors MelanocytesMelanocytes  Contain pigment melanin  Scattered throughout basale layer

9. Stratum Spinosum “ Spiny Layer”“ Spiny Layer” Produced by division of stratum germinosumProduced by division of stratum germinosum 8-10 layers of keratinocytes bound by desmosomes8-10 layers of keratinocytes bound by desmosomes Cells begin to shrink until cytoskeletons stick out (spiny)Cells begin to shrink until cytoskeletons stick out (spiny) Cells continue to divide – increasing thickness of skinCells continue to divide – increasing thickness of skin Langerhans CellsLangerhans Cells  Active in immune response

10. Stratum Granulosum “Grainy Layer”“Grainy Layer” Produces KeratinProduces Keratin KeratinKeratin  Tough, fibrous protein  Makes up hair, nails Cells dehydrate & dieCells dehydrate & die Create tightly interlocked layer of keratinCreate tightly interlocked layer of keratin

11. Stratum Lucidum “Clear Layer”“Clear Layer” Found only in thick skinFound only in thick skin Thick SkinThick Skin  Palms of hands  Soles of feet  5 layers of keratinocytes Covers stratum granulosumCovers stratum granulosum Cells are flat, dense, filled with keratinCells are flat, dense, filled with keratin

12. Stratum Corneum “Horny Layer”“Horny Layer” Exposed surface of skinExposed surface of skin Composed of dead cellsComposed of dead cells 15-30 layers of keratinized cells15-30 layers of keratinized cells Water resistantWater resistant Shed & replaced every 2 weeksShed & replaced every 2 weeks

14. Dermis Collagen, elastin fibers– scatteredCollagen, elastin fibers– scattered

15. Dermal-epidermal junction Dermal papillae: parallel rows of peg-like projectionsDermal papillae: parallel rows of peg-like projections –Unique to each individual=Fingerprints

16. Dermis Specialized structures:Specialized structures: –Hair follicle: cells of the epidermis extend into the dermis forming a small tube –Hair bulb: base of the follicle –Hair papilla: cluster of cells (live); nourished by BV’s –Root: part of hair hidden in follicle –Shaft: visible part of hair

19. Dermis Specialized Structures (continued)Specialized Structures (continued) –Arrector pili: tiny, smooth muscle attached to base of dermal papillae & side of hair follicle Contracts: pulls on both simultaneously>>goosebumpsContracts: pulls on both simultaneously>>goosebumps

21. Nails Plates of epithelial cells with keratinPlates of epithelial cells with keratin Protect distal end of phalangesProtect distal end of phalanges Cells are keratinized in nail rootCells are keratinized in nail root Nail growth occurs in lanulaNail growth occurs in lanula Cuticle is fold of stratum corneum on proximal end of nailCuticle is fold of stratum corneum on proximal end of nail

22. Specialized Structures of the Dermis Sebaceous GlandsSebaceous Glands –Secrete oil (sebum) for hair/skin –Ducts open into hair follicles –Production controlled by hormones –Accumulated sebum enlarges ducts>>white heads –Darkened sebum>>black head

24. Specialized Structures of Dermis Sudoriferous GlandsSudoriferous Glands –Eccrine Glands WidespreadWidespread Watery Fluid; sweatWatery Fluid; sweat Stimulated by increased body temperatureStimulated by increased body temperature –Apocrine Glands Armpits/GenitalsArmpits/Genitals Thick/milky fluidThick/milky fluid Odor if bacteria presentOdor if bacteria present Stimulated by nerves during play, stress, sexual activityStimulated by nerves during play, stress, sexual activity

26. Pacinian Corpuscle: deep in the dermis; detects pressure

27. Close to the surface; light touch

28. Krause’s end bulb: touch/ low frequency vibration; cold

31. Thin Skin

32. Thick Skin

33. BlistersBlisters  Friction separates layers of epidermis or epidermis from dermis  Tissue fluid collects in space CallusesCalluses  Caused by pressure  Increase in pressure causes increased mitosis  Increased mitosis creates thicker epidermis Conditions

34. Conditions ImpetigoImpetigo Pink, water-filled lesionsPink, water-filled lesions Caused by staphylococcus infectionCaused by staphylococcus infection PsoriasisPsoriasis Chronic conditionChronic condition Caused by overproduction of skin cellsCaused by overproduction of skin cells

35. Excoriation Epidermis is missing, dermis is exposedEpidermis is missing, dermis is exposed Caused by mechanical means (scratching, abrasions)Caused by mechanical means (scratching, abrasions)

36. Excoriation

37. Ulcer Craterlike lesion caused by disintegration of the skinCraterlike lesion caused by disintegration of the skin Pressure-relatedPressure-related

38. Ulcer

39. Bed Sore

40. Fissure Linear crack or break from epidermis to dermisLinear crack or break from epidermis to dermis Caused by dry skinCaused by dry skin

41. Fissures

42. Burns Classified according to severityClassified according to severity Infection most important threat; leading cause of deathInfection most important threat; leading cause of death Rule of NinesRule of Nines  Estimates volume of fluid loss  Determines how much body surface is burned  Body divided into 11 areas (each 9% of body)  1% area surrounding genitals

44. First Degree Burn Epidermis onlyEpidermis only

46. First Degree Burn

48. Second Degree Burn Deeper layers of epidermisDeeper layers of epidermis Blisters possibleBlisters possible Very painful – exposed nerve endingsVery painful – exposed nerve endings

50. Second Degree Burn

53. Third Degree Burn Complete destruction of the epidermisComplete destruction of the epidermis May extend into dermisMay extend into dermis

54. Third Degree Burn Nerve endings destroyed – not painful (initially)Nerve endings destroyed – not painful (initially)

55. Third Degree Burns

56. Third Degree Becomes painful w/ regenerationBecomes painful w/ regeneration Skin grafts neededSkin grafts needed

59. Skin graft donor site: about halfway through the initial healing stage

60. Skin Cancer A B C D for cancerA B C D for cancer A = AsymmetryA = Asymmetry  Are all sides the same? B = BorderB = Border  Is the border smooth? C = ColorC = Color  Are there areas of different color? D = DiameterD = Diameter  Larger than a pencil eraser?

61. Basal Cell Carcinoma Most CommonMost Common Stratum Basale cells involvedStratum Basale cells involved Appear on sun exposed areas of faceAppear on sun exposed areas of face Slow growingSlow growing 99% cure rate99% cure rate

62. Squamous Cell Carcinoma Stratum Spinosum cells involvedStratum Spinosum cells involved Appears on scalp, ears, dorsum of hands, lower lipAppears on scalp, ears, dorsum of hands, lower lip Fast growingFast growing Metastasizes to surroundingMetastasizes to surrounding lymph nodes lymph nodes High cure rate w/ early detectionHigh cure rate w/ early detection

64. Malignant Melanoma 5% of all cancers5% of all cancers DNA of melanocytes damagedDNA of melanocytes damaged Metastasizes rapidly to lymph nodesMetastasizes rapidly to lymph nodes and blood vessels and blood vessels 50% survival rate50% survival rate