AQA GCSE Biology Past Paper Questions PDF

Chapter 5: Communicable diseases Knowledge organiser Communicable diseases Detection and identification of plant diseases Communicable diseases can be spread from one organism to another....

Chapter 5: Communicable diseases Knowledge organiser Communicable diseases Detection and identification of plant diseases Communicable diseases can be spread from one organism to another. Signs that a plant is diseased Ways of identifying plant diseases stunted growth gardening manuals and websites Viruses live and reproduce rapidly inside an organism’s cells. This can damage or destroy the cells. spots on leaves laboratory testing of infected plants areas of rot or decay testing kits containing monoclonal antibodies e s Spread by Symptoms Virus fever growths (Chapter 9 Monoclonal antibodies) inhalation of droplets produced by malformed stems or leaves red skin rash measles infected people when sneezing and  complications can be fatal – young children are vaccinated discolouration coughing to immunise them against measles pest infestation flu‑like symptoms at first HIV (human sexual contact virus attacks the body’s immune cells, which can lead to immunodeficiency exchange of body fluids (e.g., blood AIDS – where the immune system is so damaged that it virus) when drug users share needles) cannot fight off infections or cancers Controlling the spread of communicable disease  direct contact of plants with There are a number of ways to help prevent the spread of communicable diseases from one organism to another. TMV (tobacco infected plant material  mosaic pattern of discolouration on the leaves – where mosaic virus –  animal and plant vectors chlorophyll is destroyed Hygiene Isolation Controlling vectors Vaccination plants)  soil: the pathogen can remain in soil reduces plant’s ability to photosynthesise, affecting growth Hand washing, disinfecting Isolation of infected If a vector spreads a Vaccination can protect for decades surfaces and machinery, individuals – people, disease destroying or large numbers of keeping raw meat separate, animals, and plants can be controlling the population individuals against covering mouth when isolated to stop the spread of the vector can limit the diseases. Bacteria reproduce rapidly inside organisms and may produce toxins that damage tissues and cause illness. coughing/sneezing, etc. of disease. spread of disease. e ria Spread by Symptoms Prevention and treatment Bact Salmonella bacteria and the toxins they produce cause bacteria in or on food that fever poultry are vaccinated against Key terms Salmonella Make sure you can write a definition for these key terms. is being ingested abdominal cramps Salmonella bacteria to control spread vomiting bacterium communicable disease fungicide fungus diarrhoea isolation mimic pathogen protist direct sexual contact – treatment with antibiotics (many thick yellow or green antibiotic-resistant strains have sexually transmitted disease (STD) toxin vaccination vector virus gonorrhoea is a sexually discharge from the vagina gonorrhoea appeared) transmitted disease or penis barrier methods of contraception, (STD) pain when urinating such as condoms i Fung Spread by Symptoms Prevention and treatment  purple or black spots on leaves, fungicides which turn yellow and drop early rose black spot water and wind  affected leaves removed and  reduces plant’s ability to destroyed photosynthesise, affecting growth sts Proti Spread by Symptoms Prevention and treatment mosquitos feed on the blood of infected people  recurrent  prevent mosquito vectors and spread the protist pathogen when they feed breeding episodes of malaria on another person – organisms that spread fever  mosquito nets to prevent bites disease by carrying pathogens between people  can be fatal  anti-malarial medicine are called vectors Chapter 5: Communicable diseases Retrieval questions Learn the answers to the questions below then cover the answers column with a piece of paper and write as many as you can. Check and repeat. B5 questions Answers a disease that can be transmitted from one organism to 1 What is a communicable disease? another Put paper here 2 What is a pathogen? a microorganism that causes disease 3 Name four types of pathogen. bacteria, fungi, protists, viruses 4 How can pathogens spread? air, water, direct contact 5 How do bacteria make you ill? Put paper here produce toxins that damage tissues reproduce rapidly inside cells, damaging or 6 How do viruses make you ill? destroying them 7 Name three examples of viral diseases. measles, HIV, tobacco mosaic virus Put paper here 8 Name two examples of bacterial diseases. Salmonella, gonorrhoea Name four methods of controlling the spread of good hygiene, isolating infected individuals, controlling 9 communicable disease. vectors, vaccination Put paper here malaria – caused by a protist pathogen that is spread 10 Describe an example of a protist disease. from person to person by mosquito bites, and causes recurrent fevers rose black spot – spread by water and wind, and 11 Describe an example of a fungal disease in plants. affects plant growth by reducing a plant’s ability to photosynthesise Put paper here gardening manuals and websites, laboratory testing, 12 How can the cause of a plant disease be identified? monoclonal antibody kits areas of decay, discolouration, growths, malformed 13 How can plant diseases be detected? stems or leaves, presence of pests, spots on leaves, and stunted growth