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Student name: DTT Booster AQA CORE Science Biology Diagnosis Test –Infectious Diseases Question Topic Total Marks 1 Pathogens 1 2 Immunity 3 3 White blood cells 3 4 Bacteria and viruses 2 5 -QWC Vaccination 6 My Mark R A G 15 Areas to improve: Commissioned by The PiXL Club Ltd. February 2016 © Copyright The PiXL Club Ltd, 2016 This resource is strictly for the use of member schools for as long as they remain members of The PiXL Club. It may not be copied, sold nor transferred to a third party or used by the school after membership ceases. Until such time it may be freely used within the member school. All opinions and contributions are those of the authors. The contents of this resource are not connected with www.pixl.org.uk PiXL Club Ltd, Company number 07321607 nor endorsed by any other company, organisation or The institution. www.pixl.org.uk The PiXL Club Ltd, Company number 07321607 Diagnosis Test – AQA CORE Science Biology - infectious Diseases (15 marks) 1. What is a 'pathogen'? (circle the correct answer) A. B. C. D. A disease-causing microorganism. A type of disease that infects microorganisms. A disease that spreads to communities around the world. A type of medicine that treats the symptoms of a disease. (1 mark) 2. Complete the sentences with the words in the box below, the words may be used once, more than once or not at all. Inactivated antibiotic antigen antibody antibodies immunity The immune system of the body produces specific …………………………… to kill a particular pathogen. This leads to ……………….. from that pathogen. In some cases, dead or ……………….. pathogens stimulate ………………… production. (3 marks) 3. Explain how white blood cells protect humans from infectious diseases. …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… (3 marks) 4. Why do bacteria and viruses make us feel ill when they enter the body? …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… (2 marks) 1 © Copyright The PiXL Club Ltd, 2016 5. QWC: Polio and TB are two diseases that have almost been totally eradicated from the world due to vaccination programmes. Explain how vaccination makes a person immune to an infectious disease and reduces the change of epidemics or pandemics. …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… (6 marks) 2 © Copyright The PiXL Club Ltd, 2016 SOLUTIONS Diagnosis Test – AQA CORE SCIENCE Biology - Infectious Diseases (15 marks) 1. a. What is a 'pathogen'? (circle the correct answer) A. B. C. D. A disease-causing microorganism A type of disease that infects microorganisms. A disease that spreads to communities around the world. A type of medicine that treats the symptoms of a disease. (1 mark) b. Complete the sentences with the words in the box below; the words may be used once, more than once or not at all. inactivated antibiotic antigen antibody antibodies immunity The immune system of the body produces specific antibodies to kill a particular pathogen. This leads to immunity from that pathogen. In some cases, dead or inactivated pathogens stimulate antibody production. (3 marks) 2. Explain how white blood cells protect humans from infectious diseases. • They can ingest/engulf pathogens and digest them. • They can produce antibodies that destroy or inactivate the pathogen. • They can produce antitoxins to neutralize the toxins released by the pathogen. (3 marks) 3. Why do bacteria and viruses make us feel ill when they enter the body? • Bacteria produce toxins/poisons that and these make us feel ill. • Viruses live inside cells and they damage the cells when they reproduce/ they also produce toxins that make us ill. (2 marks) © Copyright The PiXL Club Ltd, 2016 1 SOLUTIONS 4. QWC: Polio and TB are two diseases that have almost been totally eradicated from the world due to vaccination programmes. Explain how vaccination makes a person immune to an infectious disease and reduces the chance of epidemics or pandemics. QWC Suggested marking guidance (Total 6 marks) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Teachers should and apply a ‘best-fit’ approach to the marking. 0 marks No relevant content. Level 1 (1-2 marks) Mention what vaccines are or how white blood cells work or what antibodies are. The spelling, punctuation and grammar are very weak. Level 2 (3-4 marks) Level 3 (5-6 marks) Describe briefly how vaccines work and Explain how vaccines work and how white blood cells work and what how white blood cells work and antibodies are. what antibodies are and how they There is reasonable accuracy in work. The answer shows almost faultless spelling, punctuation and grammar, spelling, punctuation and although there may still be some grammar. errors. • A dead/ weakened /inactive form of pathogen/microorganism is introduced/injected into the body. • This stimulates white blood cells (WBC)/lymphocytes. • They produce antibodies to destroy the infection. • The WBC produce antibodies more rapidly if the person is re-infected. (Idea of memory cells recognising the pathogen) • The vaccination programme means less people will become infected by a pathogen. • This means that they cannot pass it to other people so less are infected and there is less chance of the disease spreading. © Copyright The PiXL Club Ltd, 2016 2 SOLUTIONS © Copyright The PiXL Club Ltd, 2016 2 SOLUTIONS Final Test – AQA CORE SCIENCE Biology - Infectious Diseases (15 marks) a. What is an ‘antigen’? (circle the correct answer) A. B. C. D. A chemical released by a white blood cell disease. A protein on the surface of a pathogen. A medicine that treats a bacterial infection. A type of medicine that treats the symptoms of a disease. (1 mark) b. Complete the sentences with the words in the box below, the words may be used once, more than once or not at all. antigens antitoxins pathogens antibodies antibiotics White blood cells work in three ways; they can ingest or engulf pathogens and destroy them by digesting them. White blood cells can also produce antibodies to destroy particular pathogens by clumping them together and destroying them. They also produce antitoxins that counteract the toxins released by pathogens. (3 marks) 3. Explain the process of vaccination and how it helps prevent illness. Any 3 from: • A dead/ weakened /inactive form of pathogen/microorganism is introduced/ injected into the body. • This stimulates the white blood cells/lymphocytes. • They produce antibodies. • The antibodies made quickly when a person is re-infection (idea of memory cells). (3 marks) 4. Explain how diseases caused by bacteria are usually treated by doctors? • They use antibiotics (accept named example e.g. penicillin.) • These kill/destroy the bacteria. (2 marks) © Copyright The PiXL Club Ltd, 2016 1 SOLUTIONS 5. QWC: Pathogens like bacteria and viruses can cause illness and disease. White blood cells can help to protect us from disease. Explain how bacteria and viruses can make us ill and how white blood cells protect us from disease. QWC Suggested marking guidance (Total 6 marks) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Teachers should apply a ‘best-fit’ approach to the marking. 0 marks Level 1 (1-2 marks) No relevant content. Description of how bacteria or viruses make us ill or mention of how white blood cells work The spelling, punctuation and grammar are very weak. Level 2 (3-4 marks) Level 3 (5-6 marks) Description of how bacteria or viruses Explain how bacteria and viruses make us ill and how white blood cells make us ill and how white blood work and what antibodies are. cells work and what antibodies are There is reasonable accuracy in and how they work. The answer shows almost faultless spelling, punctuation and grammar, spelling, punctuation and although there may still be some grammar. errors. • Bacteria produce toxins/poisons and these make us feel ill. • Viruses live inside cells and they damage the cells when they reproduce/ they also produce toxins that make us ill. • White blood cells can ingest/engulf pathogens and digest them. • They can produce antibodies that destroy or inactivate the pathogen. • They can produce anti toxins to neutralize the toxins released by the pathogen. • The WBC produce antibodies more rapidly if a person is re-infected. (Idea of memory cells recognising the pathogen) © Copyright The PiXL Club Ltd, 2016 2 Student name: DTT Booster AQA CORE Science Biology Final Test - Infectious diseases Question Topic 1 Antigens Total Marks 1 2 White blood cells 3 3 Vaccination 3 4 Treating disease 2 5 - QWC Pathogens and white blood cells 6 My Mark R A G 15 Areas to improve: Commissioned by The PiXL Club Ltd. February 2016 © Copyright The PiXL Club Ltd, 2016 This resource is strictly for the use of member schools for as long as they remain members of The PiXL Club. It may not be copied, sold nor transferred to a third party or used by the school after membership ceases. Until such time it may be freely used within the member school. All opinions and contributions are those of the authors. The contents of this resource are not connected with nor endorsed by any other company, organisation or institution. www.pixl.org.uk www.pixl.org.uk The PiXL Club Ltd, Company number 07321607 The PiXL Club Ltd, Company number 07321607 Final Test – AQA CORE SCIENCE Biology - Infectious Diseases (15 marks) 1. What is an ‘antigen’? (circle the correct answer) A. B. C. D. A chemical released by a white blood cell disease. A protein on the surface of a pathogen. A medicine that treats a bacterial infection. A type of medicine that treats the symptoms of a disease. (1 mark) 2. Complete the sentences with the words in the box below, the words may be used once, more than once or not at all. antigens antitoxins pathogens antibodies antibiotics White blood cells work in three ways; they can ingest or engulf …..…….…. and destroy them by digesting them. White blood cells can also produce ……………….… to destroy particular pathogens by clumping them together and destroying them. They also produce …………...……… that counteract the toxins released by pathogens. (3 marks) 3. Explain the process of vaccination and how it helps prevent illness. …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… (3 marks) 4. Explain how diseases caused by bacteria are usually treated by doctors. …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… (2 marks) 1 © Copyright The PiXL Club Ltd, 2016 5. QWC: Pathogens like bacteria and viruses can cause illness and disease. White blood cells can help to protect us from disease. Explain how bacteria and viruses can make us ill and how white blood cells protect us from disease. …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………………… (6 marks) 2 © Copyright The PiXL Club Ltd, 2016 The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL 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February 2016 © Copyright The PiXL Club Ltd, 2016 How to deliver the DTT Booster • Administer the short diagnosis test. • Mark the test. • Work through the therapy slides completing the model questions. • Complete the question slides for students to self or peer assess. • Administer the final test. B1.1.2 How our bodies defend themselves against infectious diseases Pathogens and defence Pathogens: Microorganisms that cause Model Question: Describe two ways that white blood cells disease. protect us from disease. Bacteria: Reproduce rapidly, make toxins, are smaller than plant or animal cells e.g. typhoid, Model Answer: cholera. • They can engulf or ingest microbes Viruses: Need to reproduce inside other cells, • They can produce antibodies always damage cells and are much smaller • They can produce antitoxins than bacteria e.g. colds, measles. Infectious: pathogen can be passed on by: Droplet infection in the air, direct contact, a break in skin, contaminated food or drink. Defence against infection 1.Physical barriers – prevent pathogens getting in. 2.Chemical defences – kill pathogens before they harm us. CLICK to reveal MODEL ANSWER White blood cells: • Ingest pathogens and destroy them. • Produce antibodies to destroy particular pathogens. • Produce antitoxins that counteract the toxins released by pathogens. http://image.slidesharecdn.com/11immunity-111013102909-phpapp01/95/y8-humans-11-immunity-7-728.jpg?cb=1318504753 B1.1.2 How our bodies defend themselves against infectious diseases Antibiotics and Resistance Semmelweis: recognised the importance of hand washing to prevent spreading of some infectious diseases. Insisting doctors wash hands before examinations has greatly reduced deaths. Model Question: Why do we have to keep developing new antibiotics? (3 marks) Model Answer Bacteria develop resisitance so are no Painkillers relieve symptoms of a disease but do longer killed therefore we need to make new antibiotics to kill the new resistant not kill the pathogen. strains. Antibiotics work inside the body to kill bacteria that cause diseases by damaging the bacterial cells – they don’t work on viruses as viruses live inside body cells. Specific bacteria should be treated with specific antibiotics – overuse or incorrect use has increased the rate of antibiotic resistant strains of bacteria. MRSA has developed resistance as a result of natural selection. Doctors now avoid overuse of antibiotics. CLICK to reveal MODEL ANSWER Mutations of pathogens produces new strains. • Antibiotics do not work against them • They spread rapidly because there is no treatment and people are not immune. • Natural selection occurs: • Only resistant survive • Resistant reproduce • All new ones are resistant strains http://image.slidesharecdn.com/11immunity-111013102909-phpapp01/95/y8-humans-11-immunity-7-728.jpg?cb=1318504753 B1.1.2 How our bodies defend themselves against infectious diseases Drugs and immunity Testing Antibiotics and disinfectants Petri dishes with sterile culture media are inoculated (have bacteria added) with sterile loops. Petri dish lids should be taped and the dish grown at 25◦C. This would reduce the risk of growing bacteria that would be harmful to humans. Immunity • Antigens – unique proteins on a pathogen cell surface. • White blood cells (WBCs) produce antibodies to join up with antigens on a pathogen. • White blood memory cells – immunity. Vaccinations • Given a weakened/dead form of the pathogen. • WBC’s produce antibodies. Pathogen is destroyed. • If come across real pathogen WBC’s can produce antibodies quickly. MMR vaccine is used to protect children against measles, mumps and rubella. Some viruses mutate often and the immune system (WBC’s) doesn’t recognise them so new vaccines have to be made for them e.g. flu. Model Question: Flu is caused by a virus, many people ask for antibiotics when they have flu. Explain why antibiotics cannot be used to cure the flu. Model Answer: • Because viruses live inside cells. • The antibiotic cannot get to the virus. • To destroy the virus the drug would have to destroy the cell. • Antibiotics are only effective against bacteria. CLICK to reveal MODEL ANSWER B1.1.2 How our bodies defend themselves against infectious diseases - Questions 1. What is a pathogen? 2. How do bacteria and viruses make us feel ill? 3. How do white blood cells help to defend against pathogens? 4. How does immunity develop? 5. How are painkillers useful? 6. What are antibiotics and what can they be used for? 7. What is one of the impacts of the overuse of antibiotics? 8. Why is it so difficult to treat viral infections? 9. Describe the action vaccinations have on the body? B1.1.2 How our bodies defend themselves against infectious diseases - Answers 1. What is a pathogen? It is a microorganism that causes an infectious disease. 2. How do bacteria and viruses make us feel ill? They reproduce in the body damaging cells and/or releasing toxins. 3. How do white blood cells help to defend against pathogens? They ingest pathogens to destroy them, produce antibodies and/or antitoxins. 4. How does immunity develop? Antigens – are unique proteins on a pathogen cell surface, white blood cells produce antibodies to join up with antigens on a pathogen. If a person becomes re-infected the memory white blood cells produce antibodies quickly because they recognise the pathogen. 5. How are painkillers useful? They relieve symptoms of an infection or illness. 6. What are antibiotics and what can they be used for? Medicines that work inside the body to kill bacteria that cause diseases by damaging the bacterial cells. 7. What is one of the impacts of the overuse of antibiotics? Overuse of antibiotics can cause antibiotic resistant bacteria to develop. 8. Why is it so difficult to treat viral infections? Viruses live inside body cells. 9. Describe the action vaccinations have on the body? Given a weak/dead form of the pathogen. White blood cells (WBC’s) produce antibodies/toxins so when the body gets infected the pathogen is destroyed. Memory WBC recognise the pathogen if reinfection occurs. Final test DTT Booster • Students now complete the final test. • Compare this to what they achieved in the diagnostic test.