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I/GCSE Biology: Treating and preventing disease

Illness, Defense on bacteria & jab

January 10, 2022

Feeling ill

Medicines help to relieve symptoms (e.g. lozenges for sore throat) but don’t not kill the pathogen

Killing Bacteria

  • Antibiotics (AB) =  medicines that help cure diseases caused by B
  • AB kill B inside body
  • Penicillin was first AB discovered
  • AB can’t kill viruses
  • V’s  live and reproduce inside cells = hard to develop a medicine which kills the V but doesn’t damage body cells or tissues
  • Effect of a AB measured in a lab
  • Done by placing small discs of paper containing antibiotics on a dish containing B growing on gel
  • Clear zone is where AB has been killed
  • Results in body may be different to results on gel (body is more complicated)

A quick Jab

  • Immunity can be gained w/o ever having the disease
  • When baby – immunised against whooping cough, measles and polio
  • Immunisation (vaccination) = injecting or swallowing a vaccine.
  • Dead or inactive form of the pathogen.
  • Vaccine doesn’t make you ill but WBC still produce Antibodies and destroy the pathogen.
  • Step 1 – Weak or dead microbes are injected into body
  • Step 2 – Antibodies produced which destroy microbes and their toxins
  • Step 3 – You’re immunised, next time REAL disease comes, antibodies are released before you become ill.

Well done!