Health, disease and the development of medicines

• what is health

  • a state of complete physical, mental and social well-being as defined by the World Health Association (WHO)
• what is a communicable disease

  • a disease that can be spread from organism to organism
• what is a non-communicable disease

  • a disease that can't be spread but is cause by a problem in the body
• Explain why the presence of one disease can lead to a higher susceptibility to other diseases

  • disease can weaken you immune system so it will be less likely to fight other diseases as well
• what is a pathogen

  • a disease-causing organism such as viruses, bacteria, fungi and protists
• what does cholera cause

  • diarrhoea
• is cholera a bacteria, virus, fungi or protist

  • bacteria
• how is cholera spread

  • through water
• what does tuberculosis cause

  • lung damage
• is tuberculosis a bacteria, virus, fungi or protist

  • bacteria
• how is tuberculosis spread

  • airborne
• what does chalara ash dieback cause

  • leaf loss and bark lesions
• is chalara ash dieback a bacteria, virus, fungi or protist

  • fungi
• how is chalara ash dieback spread

  • airborne
• what does malaria cause

  • damage to blood and liver
• is malaria a bacteria, virus, fungi or protist

  • protists
• how is malaria spread

  • animal vectors , e.g. mosquitoes
• what do Helicobacter cause

  • stomach ulcers
• is Helicobacter a bacteria, virus, fungi or protist

  • bacteria
• how is Helicobacter spread

  • oral transmission
• what does ebola cause

  • haemorrhagic fever
• is Ebola a bacteria, virus, fungi or protists

  • virus
• how is ebola spread

  • body fluids
• how can spread of cholera be reduced

  • Good hygiene, access to clean drinking water
• how can spread of tuberculosis be reduced

  • good ventilation
  • natural light - UV light kills TB bacteria
  • good hygiene
• how can spread of malaria be reduced

  • vector control - eradicating mosquitoes
  • use of bed nets
  • wear protective clothing
  • insect repellents
• how can spread of helicobacter be reduced

  • Washing your hands thoroughly with soap and water
  • Eating food that has been properly cooked
  • Drinking clean, safe water
• describe the virus life cycle: lysogenic pathway

  • viral genetic material inserts into chromosomes/genome
  • genetic material gets replicated along with the host DNA every time the host cell divides
  • a trigger causes the viral genetic material to leave the chromosome/genome
  • enters the lytic pathway
• describe the virus lifecycle: lytic pathway

  • virus attaches itself to a specific host cell and injects its genetic material in the cell
  • virus uses proteins and enzymes in host cell to replicate its genetic material and produce the components of new viruses
  • viral components are assembled
  • host cell splits open releasing the new viruses to infect more cells.
• what can chlamydia cause

  • it can result in infertility in men and women
• is chlamydia a bacteria, virus, fungi or protist


  • bacteria
• what does chlamydia do

  • it reproduces inside host cells like a virus
• how can the spread of chlamydia be reduced

  • wearing a condom
  • reducing sexual contact
• what does HIV do

  • hills white blood cells, weakening the immune system
• how is chlamydia spread

  • bodily fluids
• how is HIV spread

  • infected bodily fluids
• what can HIV eventually led to

  • AIDS
• wat can reduce the spread of HIV

  • wearing a condom
  • avoid sharing needles
• what are physical defences plants have against pathogens

  • waxy cuticle: covers leaves and plants acting as a barrier to stop pathogens entering
  • cell wall: stops pathogens entering
  • bark
• what are chemical defences plants have against pathogens

  • aspirin
  • quinine
  • these stop the pathogens from feeding on leaves