Treating, curing and preventing diseases

• White blood cells kill pathogens by consuming them, producing antibodies and producing antitoxins
• The skin acts as a barrier to pathogens.
• The stomach produces hydrochloric acid to kill bacteria.
• Antibiotics are drugs that destroy or stop the growth of bacteria.
• Mucus traps pathogens.
• Vaccinations involve injecting a small amount of dead or inactive pathogens
• what are disadvantage of vaccines?


  They don't always work and you could have a bad reaction to it however it is very rare.
• Antibiotics kill or prevent the growth of bacteria.
• Some bacteria are resistant to antibiotic as they can mutate and not be killed by an antibiotic.
• Aspirin is a painkiller and was developed from willow bark.
• Digitalis is used to treat heart conditions and it is developed from foxgloves.
• Penicillin is made from Penicillium mold.
• Alexander Fleming found penicillin.
• In preclinical testing, the drug is tested on animals to see if it is safe and effective.
• Monoclonal Antibodies are identical copies of one type of antibody.
• Antibodies are proteins produced by a type of white blood cell called lymphocyte.
• Steps of making monoclonal antibodies:

  1. Antigen is injected into a mouse.
  2. The lymphocytes and the tumour cell fuses to make a hybridoma.
  3. The hybridoma cell divides and produces the antibodies.
  4. The antibodies are collected and purified.
• What are uses of monoclonal antibodies?

  • Pregnancy test kits
  • Cancer diagnosis and treatments
  • Diagnose infections such as HIV ,AIDS, chlamydia etc.
• A hormone called HCG is found in the urine of women who are pregnant.
• Monoclonal antibodies treat cancer by being bound to a radioactive substance, a toxic drug or a chemical which stops cells growing and dividing.
• Bacteria produces toxins (poisions) that damages tissues and makes us ill.
• Viruses damages your cell by reproducing microorganism.
• What are symptoms of gonorrhea ?

  pain when urinating and thick yellow discharge
• What is a communicable disease?

  A disease that can be spread from one person to another
• How does white blood cells kill pathogens :

  1. Consuming pathogens (phagocytosis)
  2. Producing antibodies
  3. Producing antibodies
• Explain two ways our skin protects the body against pathogens.

  • Acts as a physical barrier
  • Produces anti-microbial bacteria that kill bacteria
• How to platelets protect our bodies against pathogens?

  • They make protein fibres that form a mesh over the wound forming clots
  • A scab is formed
• Our nose has cilia and mucus to trap pathogens from the air.

  They are release when we sneeze or blow our noses
• What does digitalis treat?

  Heart failure
• Steps for white blood cells attacking pathogens :

  1. Consuming microbes - White blood cells engulf pathogens (phagocytosis)
  2. Producing antibodies - Antibodies bind to the specific antigen of the pathogen and produce memory cells
  3. Producing anti-toxins - The antitoxins neutralise the toxins produced by the pathogens.
• What happens when a vaccine is injected into a person?

  • WBCs produces antibodies to attach to the microbe.
  • Antibodies attach to the specific antigen of the microbe and produce memory cells
  • If the same microbe then attacks the body memory cells produce antibodies.
• Why can't medicine not kill viruses ?

  • Viruses invade our cells
  • Our cells will be harmed
• What are causes of antibiotic resistance ?

  • Overprescription
  • Lack of hygiene
• Effective - drug prevents or cures disease

  Safe - drug must not be toxic or cause side effects

  Stable - need to be able to use the medicine under normal conditions and store it

  Dosage - concentration that is given
• Steps of testing new drug :

  1. Preclinical tests on humans cells and tissues
  2. Preclinical test on live animals
  3. Clinical trials on human volunteers
• What is the purpose of a placebo ?

  To compare effects of the drug
• Steps of clinical trials on human volunteers :

  1. healthy volunteers
  2. people suffering from the illness
  3. double blind trials