Presenting What Causes ALS Christopher Link Ph D Associate Professor Department of Integrative Physiology Monday September 8 12 00 p m GOLD Building MCDB Porter Room A2B70 Amyotrophic 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 html Copyright 2008 Pearson Education Inc Human Anatomy 5e by Marieb Mallatt and Wilhelm publishing as Benjamin Cummings Can 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 organ B Yes all membranes are there own organ because they consist of multiple tissue layers C No an organ has to have more than just 2 tissue layers D No it would have to be part of an anatomical system to be considered an organ Human Anatomy 5e by Marieb Mallatt and Wilhelm Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Cutaneous Membrane Integument Skin cutaneous membrane organ Human Anatomy 5e by Marieb Mallatt and Wilhelm Serous mucous membranes are one component of an organ Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Integumentary System Study tip 3 Talk to yourself For each powerpoint slide describe what you see and what you know about the structures on those images THINK ABOUT THIS What causes the skin on your hands and feet to wrinkle the prune effect when you spend too much time in water ORGAN a part of the body formed of 2 or more tissue layers that work together to perform specific functions Examples stomach skin lung sweat gland etc Copyright 2005 Pearson Education Inc publishing as Benjamin Cummings Integument Covers surface of entire body 7 of total body weight Varies in thickness Layer 1 epithelial tissue Layer 2 Connective tissue Copyright 2005 Pearson Education Inc publishing as Benjamin Cummings Which of the following statements is NOT true of the skin A the skin is involved in gas exchange between the air and deeper tissues B the skin can excrete several liters of fluid each day C the skin is a water resistant organ D the skin has sensory structures E the skin protects deeper tissues from bacteria Functions of the Integument 1 Water resistant structure Sebum oil glyocolipids create barrier 2 Excretion of liquids and salts 3 Sensory Receptors for touch temp pain Allow interaction w world around us 4 Body temp regulation Extensive capillary network evaporation and hair all play a role 5 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 production Figure 5 1 Skin structure Epidermis Keratinized stratified squamous epithelium Dermis Loose areolar CT Dense irregular CT Hypodermis superficial fascia Adipose CT Human Anatomy 5e by Marieb Mallatt and Wilhelm Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Thin skin Epidermis has 4 distinct layers Thick skin Epidermis has 5 distinct layers Human Anatomy 5e by Marieb Mallatt and Wilhelm Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Figure 5 3b Layers of the epidermis Stratum corneum Stratum lucidum Stratum granulosum Stratum lucidum only present in thick skin Stratum spinosum Stratum basale Dermis Human Anatomy 5e by Marieb Mallatt and Wilhelm Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Figure 5 3b Distribution of cell types in epidermis Keratinocytes most abundant Desmosomes Keratinocytes Dendritic cell Produce keratin Connected by desmosomes New cells produced at basal surface oldest cells on apical surface Replaced every 35 45 days Melanocytes Pigment producing cells Found in stratum basale Melanin granules transported to adjacent keratinocytes Merkel cells Sensory touch receptors Has associated nerve ending Stratum basale layer only Merkel cell Dendritic Langerhans cells Phagocytic cell engulf foreign material Primarily in stratum spinosum Melanocytes Melanin Human Anatomy 5e granules by Marieb Mallatt and Wilhelm Sensory nerve ending Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Dendritic cells in action Human Anatomy 5e Copyright 2008 Pearson Education Inc https www inkling com read janeways immunobiology kenneth murphy 8th chapter 9 movie 9 2 dendritic cell by Marieb Mallatt and Wilhelm publishing as Benjamin Cummings Figure 5 3b Diagram showing distribution of cell types Desmosomes Keratinocytes Dendritic cell Stratum granulosum 3 5 layers of flattened keratinocytes Cells starting to die Cells contain keratohyaline lamellated granules Several layers of cells Mostly keratinocytes Some dendritic cells Stratum spinosum Merkel cell Stratum basale Dermis 1 cell layer mostly keratinocytes and stem cells Melanocytes 10 25 Some Merkel cells Melanocytes Melanin granules b Human Anatomy 5e by Marieb Mallatt and Wilhelm Sensory nerve ending Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Keratohyaline lamellated granules Glycolipid being secreted Stratum granulosum Lamellated granules Keratohyaline granules Keratohyaline granules form keratin Stratum spinosum Lamellated granules produce a glycolipid which is moved outside of the cell Stratum basale anatomy iupui edu Human Anatomy 5e by Marieb Mallatt and Wilhelm Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Figure 5 3b Diagram showing four layers and the distribution of cell types Desmosomes Keratinocytes Langerhans cell Stratum corneum Stratum lucidum Layers of dead skin cells Stratum granulosum Stratum spinosum Merkel cell Stratum basale Dermis Melanocytes Melanin granules b Human Anatomy 5e by Marieb Mallatt and Wilhelm Sensory nerve ending Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Figure 5 4a Thick skin Epidermis Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale Dermis a Thick skin Human Anatomy 5e by Marieb Mallatt and Wilhelm Copyright 2008 Pearson Education Inc publishing as Benjamin Cummings Figure 5 4b Thin skin Epidermis Stratum corneum Stratum granulosum Stratum spinosum Stratum basale Dermis b Thin skin Human