A Level Biology Revision "Non-specific Defences Against Pathogens"

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In this video, we start looking at the body's non-specific defences against pathogens. These include the skin, mucous membranes, lysozyme and expulsive reflexes. In the next video, we look at blood clotting and inflammation. Image credits: Human Skin Structure https://commons.wikimedia.org/wiki/File:Human_skin_structure.jpg XenonR, CC BY 3.0 https://creativecommons.org/licenses/by-sa/3.0/deed.en Tear https://commons.wikimedia.org/wiki/File:Tear.jpg NessaLand, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, via Wikimedia Commons Scab https://commons.wikimedia.org/wiki/File:Hand_Abrasion_-_2_days_22_hours_12_minutes_after_injury.JPG Jpbarrass, Public domain, via Wikimedia Commons Sebaceous gland https://commons.wikimedia.org/wiki/File:407_Sebaceous_Glands.jpg OpenStax College, CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons Epidermis and dermis https://commons.wikimedia.org/wiki/File:Normal_Epidermis_and_Dermis_with_Intradermal_Nevus_10x-cropped.JPG Normal_Epidermis_and_Dermis_with_Intradermal_Nevus_10x.JPG: Kilbadderivative work: Fama Clamosa, Public domain, via Wikimedia Commons Lining of treachea https://commons.wikimedia.org/wiki/File:Trachea_(mammal)_histology_cross-section.png Magscope, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons Gastric mucosa https://commons.wikimedia.org/wiki/File:Normal_gastric_mucosa_intermed_mag.jpg Nephron, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons Sneeze https://commons.wikimedia.org/wiki/File:Sneeze.JPG James Gathany, Public domain, via Wikimedia Commons Coughing https://commons.wikimedia.org/wiki/File:Couging.jpg https://upload.wikimedia.org/wikipedia/commons/0/01/Couging.jpg