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TRYING TO INCREASE SUCCESS IN BIOLOGY? Check out Mr. W's interactive biology curriculum, . You won’t believe how much biology you — or your students — will learn. HIGH SCHOOL TEACHERS: Have your school purchase a license so all of your students can access our interactive tutorials. Learn more and sign up for a free trial at: COLLEGE PROFESSORS: Help your students master the most complex topics in biology, with interactive tutorials about DNA replication, photosynthesis, immunity, cellular respiration, and so much more. Learn more and sign for a free trial at: STUDENTS: We’ve got interactive tutorials, flashcards, AP Bio practice FRQs, videos, and more songs. Sign up at For $ you get a full year's access. BUY THE BIOMANIA BIOLOGY APP: To master the details of the immune system, to to my interactive tutorial at LYRICS It’s a dangerous world full of pathogenic germs Viruses and fungi and bacteria and worms They’re trying to invade you, to them you’re food and shelter, And once they get inside it sends your system helter skelter But you’ve got a system for fighting back, For recovering your health from infectious attack With weapons that leave these pathogens in ruins Yeah we’re talking ’bout the system that makes us immune CHORUS It’s the immune system Sworn to protect you From dangerous pathogens that try to infect you Three layers of defense keep the germs away Letting us live yet another day, Skin and mucous membranes first, then innate defenses, For fending off invaders that breach our fences, Then specific responses, with lymphocytes B and T Let’s learn about immunity! Our outermost defense is our impermeable skin Dead outer cells lined with fibrous keratin Covered with secreted lactic acid and lysozyme A bacteria dissolving enzyme At openings like noses there’s a mucus-membrane lining, A viscous protein fluid trap for pathogen confining, And pathogens that enter through the mouth can die quite miserably When they’re dissolved inside our stomach’s sour acidity. But even with these barriers, some pathogens break through Entering through cuts or riding mucus into you The next step in defense is non-specific and innate We share it with the plants and fungi and invertebrates! You’re born with these defenses that’s why they’re called “innate.” They’re implemented when infection starts, no need to wait They consist of cells and proteins that make non-specific moves Against those foreign entities that enter into you. The primary components here are white blood cells Sentinels or guards who respond when all’s not well They’re leukocytes, they fight invaders in generic ways Engulfing them or chemically blowing them away HORUS Inflammation’s a key part of the innate response You know it from the swelling and the way a wound feels hot Tissue damage from infections or injuries Causes leukocytes like mast cells to release histamines Which makes capillaries leak though vasodilation, Leads to redness and to swelling and a painful sensation Sentinel cells and tissues emit chemical alarms That draw defenders to the scene defending us from harm. The first cell to arrive could be a neutrophil The most abundant type of white blood cell They’re phagocytes,engulfing viruses and germs Devouring pathogens like robins eating worms These neutrophils gorge themselves until they die defending us Their cellular remains accumulate as pus Innate responses, they’re anything but simple Remember that each time you see the pus inside a pimple Another phagocyte is called a macrophage Which means “big eater” they attack with rage Dendritic cells are phagocytes too Patrolling ‘neath the skin and in the lungs and other tissues A fever is a body-wide systemic inflammation, The higher temperature inhibits germ replication, And might also enhance immune cells’ phagocytic action As fever ramps up our body’s chemical reactions. CHORUS Natural killer cells are also on the innate team Detecting body cells that display abnormal proteins Indicating viral infection or cancer And when they meet abnormal cells here’s their deadly answer... Full lyrics at
