10 syllabus statements
- 1. 09/04/2016 10. Diseases & immunity Syllabus statements Statements from Cambridge IGCSE Chemistry syllabus 0610 (for exams in 2016 – 2018)Image from http://classes.midlandstech.edu/carterp/courses/bio225/chap16/lecture3.htm
- 2. Diseases & immunity • Define pathogen as a disease-causing organism • Define transmissible disease as a disease in which the pathogen can be passed from one host to another • State that the pathogen for a transmissible disease may be transmitted either through direct contact, e.g. through blood or other body fluids, or indirectly, e.g. from contaminated surfaces or food, from animals, or from the air
- 3. Diseases & immunity • State that the body has defences: – mechanical barriers (skin and hairs in the nose) – chemical barriers (mucus and stomach acid) – cells (phagocytosis and antibody production by white blood cells) – which can be enhanced by vaccination • Explain the importance of good personal hygiene, hygienic food preparation, waste disposal and sewage treatment in controlling the spread of disease
- 4. Diseases & immunity • State that antibodies lock on to antigens leading to direct destruction of pathogens, or marking of pathogens for destruction by phagocytes • Explain how each pathogen has its own antigens, which have specific shapes, so specific antibodies which fit the specific shapes of the antigens are needed • Define active immunity as defence against a pathogen by antibody production in the body • Explain that active immunity is gained after an infection by a pathogen, or by vaccination
- 5. Diseases & immunity • Explain the process of vaccination: – harmless pathogen given which has antigens – antigens trigger an immune response by lymphocytes which produce antibodies – memory cells are produced that give long-term immunity • Explain the role of vaccination in controlling the spread of diseases
- 6. Diseases & immunity • Explain that passive immunity is short-term defence against a pathogen by antibodies acquired from another individual, e.g. mother to infant • State that memory cells are not produced in passive immunity • Explain the importance of passive immunity for breast-fed infants • State that some diseases are caused by the immune system targeting and destroying body cells, limited to Type 1 diabetes