9/3/20141PresentingWhat Causes ALS?Christopher Link, Ph.D.Associate ProfessorDepartment of Integrative PhysiologyMonday, September 8, 12:00 p.m.GOLD Building (MCDB/Porter), Room A2B70Amyotrophic Lateral Sclerosis is a progressive, fatal motor disease. It is characterized by dysfunction and death of motor neurons, although there is evidence that this is not solely cell-autonomous. The classic histopathology in ALS is the appearance of abnormal cytoplasmic inclusions in affected motor neurons. In almost all ALS cases, these inclusions contain an RNA-binding protein called TDP-43… More info on IPHY website: www.Colorado.edu/intphys/events/colloquium.htmlCan a membrane also be considered to be an organ? Why or why not?A. Yes; by definition a membrane could be its own organ, but may also just be part of an organB. Yes; all membranes are there own organ because they consist of multiple tissue layersC. No; an organ has to have more than just 2 tissue layersD. No; it would have to be part of an anatomical system to be considered an organCutaneousMembraneIntegument/Skin=cutaneous membrane = organSerous & mucous membranes are one component of an organ9/3/20142IntegumentarySystemStudy tip #3:Talk to yourself! For each powerpoint slide, describe what you see and what you know about the structures on those images. What causes the skin on your hands and feet to wrinkle (the prune effect) when you spend too much time in water? THINK ABOUT THIS:Copyright © 2005 Pearson Education, Inc., publishing as Benjamin CummingsORGAN: a part of the body formed of 2 or more tissue layers that work together to perform specific functionsExamples: stomach, skin, lung, sweat gland, etc9/3/20143Copyright © 2005 Pearson Education, Inc., publishing as Benjamin CummingsLayer 1 =epithelial tissueLayer 2 =Connective tissueIntegument:•Covers surface of entire body•~7% of total body weight•Varies in thickness Which of the following statements is NOT true of the skin.A. the skin is involved in gas exchange between the air and deeper tissuesB. the skin can excrete several liters of fluid each dayC. the skin is a water-resistant organD. the skin has sensory structuresE. the skin protects deeper tissues from bacteriaFunctions of the Integument1. Water-resistant structure• Sebum (oil) & glyocolipids create barrier2. Excretion of liquids and salts3. Sensory • Receptors for touch, temp & pain• Allow interaction w/ world around us4. Body temp regulation• Extensive capillary network, evaporation, and hair all play a role5. Protection• Stops & destroys bacteria• Protects from dehydration• Absorbs UV light but doesn’t completely block it• Too much damages epidermis• Some needed to assist in Vitamin D production9/3/20144Figure 5.1 Skin structure.EpidermisDermisHypodermis(superficialfascia)Keratinized stratified squamous epitheliumLoose areolar CTDense irregular CTAdipose CTHuman Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin Cummings.Thin skin:Epidermis has 4 distinct layersThick skin:Epidermis has 5 distinct layersFigure 5.3b Layers of the epidermisStratumcorneumStratumgranulosumStratumspinosumStratumbasaleDermisStratumlucidumStratum lucidum only present in thick skin9/3/20145Figure 5.3b Distribution of cell types in epidermisSensory nerve endingMelanocytesMelanin granulesMerkel cellDendritic cellKeratinocytesDesmosomesKeratinocytes: most abundant•Produce keratin•Connected by desmosomes•New cells produced at basal surface, oldest cells on apical surface•Replaced every 35-45 daysMelanocytes•Pigment producing cells•Found in stratum basale•Melanin granules transported to adjacent keratinocytesMerkel cells•Sensory touch receptors•Has associated nerve ending•Stratum basale layer onlyDendritic (Langerhans) cells•Phagocytic cell engulf foreign material•Primarily in stratum spinosumDendritic cells in actionhttps://www.inkling.com/read/janeways-immunobiology-kenneth-murphy-8th/chapter-9/movie-9-2-dendritic-cellFigure 5.3b Diagram showing distribution of cell typesSensory nerve endingMelanocytesMelanin granulesMerkel cellDendritic cellStratumgranulosumStratumspinosumStratumbasaleDermisKeratinocytesDesmosomes(b)1 cell layer:• mostly keratinocytes (and stem cells)• Melanocytes (~10-25%)• Some Merkel cellsSeveral layers of cells:• Mostly keratinocytes• Some dendritic cells3-5 layers of flattened keratinocytes• Cells starting to die• Cells contain keratohyaline & lamellatedgranules9/3/20146Keratohyaline & lamellated granules anatomy.iupui.eduKeratohyaline granulesLamellated granulesGlycolipid being secretedStratum basaleStratum granulosumStratum spinosumKeratohyaline granules form keratinLamellated granules produce a glycolipid which is moved outside of the cellFigure 5.3b Diagram showing four layers and the distribution of cell typesSensory nerve endingMelanocytesMelanin granulesMerkel cellLangerhans cellStratumcorneumStratumgranulosumStratumspinosumStratumbasaleDermisKeratinocytesDesmosomes(b)StratumlucidumLayers of dead skin cellsFigure 5.4a Thick skinStratumbasaleEpidermisDermisStratumcorneumStratumlucidumStratumgranulosumStratumspinosum(a) Thick skin9/3/20147Figure 5.4b Thin skinStratumbasaleEpidermisDermisStratumcorneumStratumgranulosumStratumspinosum(b) Thin skinWhich layer of the epidermis would you expect to thicken to form a callus?A. stratum basaleB. stratum spinosumC. stratum granulosumD. stratum lucidumE. stratum corneumFigure 5.1 Skin structure.EpidermisDermisDermal papilla-increase surface area-stronger connection to epidermisPapillary layer of dermis-loose areolar CT-CT proper9/3/20148Friction Ridges & Poreshenrytempleman.com/ridge_unit_weights_13www.cic.gc.ca/english/resources/publications/biometrics-eval/section6.asp50x magnificationPores on friction ridgesFigure 5.1 Skin structure.DermisHypodermis-adipose CTReticular layer-dense irregular CTPapillaryCopyright © 2005 Pearson Education, Inc., publishing as Benjamin CummingsFig. 5.10b First, second, and third-degree burns1stdegree  damage to epidermis2nd degree  damage to dermis3rd& 4thdegree  damage to hypodermis or deeper9/3/20149Figure 5.11 Burns. RULE OF NINES: 11 body regions, each a multiple of 9TotalsAnterior and posteriorhead and neck, 9%Anterior and posteriorarm, 18%Anterior and posteriortrunk, 36%Anterior and posteriorlower limbs, 36%(Perineum, 1%)100%41/2%Anteriortrunk, 18%9% 9%(a)