B3: Infection & Response

• Pathogen


  An organism that causes disease

  
• 4 types of pathogens

  1. bacteria

  2. viruses

  3. protist

  4. fungi

  
• Malaria


  A disease caused by mosquitoes implanting parasites in the blood.

  
• What do bacteria release to make us ill

  toxins

  
• Measles


  Virus spread by droplets from a sneeze or a cough

  Symptoms: red skin rash and a fever

  
• Rose black spot


  A fungal disease where purple or black spots develop on leaves, which often turn yellow and drop early.

  
• HIV


  A virus that attacks and destroys the human immune system.

  
• Gonorrhea


  A sexually transmitted bacterial disease that causes burning pain when urinating, and a discharge

  
• Salmonella


  Bacteria that causes food poisoning by producing toxins

  Symptoms: fever, stomach cramps, vomiting and diarrhoea

  Caused by eating food contaminated with salmonella e.g. uncooked chicken

  In the UK, most chickens are vaccinated against salmonella

  
• Tobacco Mosaic Virus


  Virus that causes discolouring in tobacco leaves by preventing the formation of chloroplasts.

  
• athlete's foot


  Fungus infection usually in the skin of the toes and soles
• Phagocytes


  white blood cells that engulf and destroy pathogens

  
• Lympocytes


  white blood cell that produce antibodies

  
• Antigens


  a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.

  
• Antibodies


  Protein that is produced by lymphocytes and that attaches to a specific antigen.

  
• stomach acid (HCl)


  hydrochloric acid that destroys pathogens

  
• specific response

  an adaptive immune response directed against a particular antigen that retains immunological memory of that antigen

  
• vaccination


  injection of a weakened or mild form of a pathogen to produce immunity

  
• Non-specific response


  Responses that are immediate and the same for all pathogens

  
• Examples of non specific immunity

  skin, tears and mucous membranes, inflammation, fever, phagocytosis.

  
• examples of specific immunity

  lymphocytes producing specific antibodies

  
• Viruses


  Viruses can only reproduce inside host cells, and they damage the cell when they do this

  VIRUSES GET INTO CELL

  
• Bacteria


  single-celled organisms that lack a nucleus; prokaryotes

  
• antibiotic


  A chemical that kills bacteria or slows their growth without harming body cells.

  
• antibiotic resistance


  overuse of antibiotic that causes the drug to no longer work

  
• Vaccination steps


  1, dead or inactive pathogen injected

  2, White blood cells

  3, Produce antibodies

  4, Which attach to the specific antigen and kill it

  5, Memory cells remain

  6, Which can produce antibodies faster and more intensely

  7, Making you immune

  
• Disease caused by viruses

  Measles, TMV and HIV
• Disease caused by a protist

  malaria
• Disease caused by bacteria

  Salmonella and Gonorrhea
• Disease caused fungus


  Rose black spot