Revision List…… Lessons to learn for test 1) Going on growing 2) Defence systems 3) Killing bacteria 4) Fighting infection 5) The battle goes on Going on growing Keywords 1. Microorganisms= Are tiny living things, so small we need a microscope to see them. 2. Microbes= Is what we sometimes call microorganisms 3. Bacteria=A microorganism that is very small, which consists of only one cell 4. Viruses=Microbes that are smaller than bacteria 5. Fungi=Are small and round, examples include yeasts and moulds Bacteria, fungi and viruses are all types of microorganism Bacteria Microorganims/Microbes Viruses Fungi Diagrams of microbes and some features 1. Bacteria Single cell No nucleus Reproduce by dividing 2. Virus The smallest microbe Not made of cells Diagrams of microbes and some features Are small 3. Fungi Are round Are single celled Many microbes are very important Fungi are used in/for: Beer Cheese Antibiotics Bacteria used in: Yogurt Cheese Revision List…… Lessons to learn for test 1) Going on growing 2) Defence systems 3) Killing bacteria 4) Fighting infection 5) The battle goes on Defence systems Keywords 1. Sexually transmitted diseases=are diseases caught through sexual intercourse without protection (condom). An example is AIDS 2. Immune system=Part of the body which fights against microbes when they get into the body 3. White blood cells=Found in the blood and whose job is to destroy microorganisms in the body 4. Antibodies=Are chemicals produced by white blood cells which attach to the outside of microbes and kill them. Defence systems Keywords 5) Immune= If your body has met a microbe before, it can make antibodies quickly so you therefore don’t get ill, you are then IMMUNE to that microbe 6) Infections=When a microorganism enters our body, we are then infected so therefore have an INFECTION 7) Pathogen= Are the bad microorganisms that cause infection Some microorganisms are very bad and cause disease 1. Tuberculosis caused by a bacteria (affects the lungs) 2 Rabies (from animal bites) is caused by a virus 3 Athletes foot is caused by a fungus How do we keep microbes out of our bodies??? 1)Skin provides a 2)Tears strong have barrier chemicals that destroy 3)Strong bacteria stomach 4)White acid blood cells destroys kill microbes microbes inside the We also have mucus in our nose and wax in our ears body So how do microbes get into our body then???? 1. From cuts in our skin 2. Dirty water 3. Contaminated food 4. Air that we breathe has microbes 5. From animal and insect bites 6. From sexual intercourse Fighting infection • If microbes penetrate the body’s barriers the immune system is used to clear up infection • White blood cells found in blood fight against microbes. They destroy microbes in 3 ways: 1. They swallow up microbes 2. Produce antibodies that attach to microbes 3. Destroy toxins made by microbes Revision List…… Lessons to learn for test 1) Going on growing 2) Defence systems 3) Killing bacteria 4) Fighting infection 5) The battle goes on Killing bacteria Keywords 1. Antiseptics=Are ointments and creams that have chemicals used kill bacteria. Are applied to cuts 2. Antibiotics=Are medicines that kill bacteria once they’ve got into our body 3. Agar plate=Has a jelly that contains food to grow bacteria in laboratories How we kill bacteria in our food and drink Chlorine is added to our We cook our food water to kill bacteria at high temperatures Antiseptics We apply antiseptics to our cuts to kill bacteria and stop infections Joseph Lister was first to use antiseptic Antibiotics The discovery of antibiotics by Fleming was by complete chance. What are antibiotics? Antibiotics are chemicals produced by fungi to kill OR stop the growth of bacteria. IMPORTANT- •Antibiotics are medicines that kill bacteria that have got inside the body. For example penicillin •THEY DO NOT KILL VIRUSES!!!!! Why do we need so many different antibiotics??? • Different antibiotics are needed because bacteria can become RESISTANT to a certain antibiotic. • This means that the antibiotic does not kill certain bacteria and it will continue to live. So we therefore use a different one. How does a bacteria become RESISTANT? 1. Because people don’t finish all their tablets. 2. Because doctors give wrong antibiotics to people 3. Because doctors give antibiotics when not needed Revision List…… Lessons to learn for test 1) Going on growing 2) Defence systems 3) Killing bacteria 4) Fighting infection 5) The battle goes on Fighting infection Keywords 1. Vaccination=When dead or inactive microbes are injected into our bodies. 2. Immunised=After our vaccination our body makes antibodies which are ready in case the disease ever infects our body. Lady Montague • In the 1700’s people were scared of catching smallpox • They had lots sores and usually died. (see picture below) • Lady Montague put some pus from one of the sores into the vein of a healthy person. • This made them slightly ill but when they recovered they were IMMUNE to smallpox What did Edward Jenner discover??? • In 1788 there was a big outbreak of smallpox • He noticed people who worked with cows only caught cowpox(milder than smallpox • So, he put cowpox pus into a healthy person to IMMUNISE them against smallpox • He called his discovery vaccination Revision List…… Lessons to learn for test 1) Going on growing 2) Defence systems 3) Killing bacteria 4) Fighting infection 5) The battle goes on The battle goes on….. Ways of preventing the spread of infection before microorganisms were identified: Case 1- The bubonic plague •The great plague was caused by bacteria in infected rats, passed to humans by rat bites. •It was passed from human to human by coughing and sneezing. How did people prevent the spread of disease from one village to another???? 1. A brave vicar persuaded people to stay in the village which stopped infection spreading 2. Their food was delivered to the edge of the village 3. They used to drop money into wells for collection by delivery people Case 2-Cholera in the water Background information •Cholera is caused by a bacteria in people’s drinking water •Back in the 1800’s people got water from pumps in the street •A clever man, Dr Snow showed how many victims of cholera lived near a single pump How did they stop cholera infection?? •By closing pumps which spread the infection •Nowadays in developing countries e.g Bangladesh cholera is controlled by 1) Adding chlorine 2) Boiling water 3) Antibiotics How the incidence of disease has changed over time What this graph shows •Firstly we see an increasing numbers of deaths up until Lady Montague’s Deaths discovery(first dotted line) •The number of deaths then decreases •The number of deaths Date further decreases following Edward Jenner’s discovery(second dotted line) Very best of luck with your test!!!!!