Defenses

• what human barriers protect the body from pathogens entering?

  skin

  nose hair

  saliva in mouth

  stomach acid
• how do white blood cells defend against pathogens?

  phagocytosis (engulf the pathogen)

  produce antibodies

  produce antitoxins
• vaccines have a inactive or dead form of the pathogen which will be used to produce antibodies against the pathogen and the memory cells will remember so in future if the same pathogen does come the body will become immune
• Antibiotics, such as penicillin, are medicines that help to cure bacterial disease by killing infective bacteria inside the body. It is important that specific bacteria should be treated by specific antibiotics.
• The use of antibiotics has greatly reduced deaths from infectious bacterial diseases. However, the emergence of strains resistant to antibiotics is of great concern.
• Herd immunity is the protection given to a population against an outbreak of a specific disease when a very high percentage of the population have been vaccinated against it. high immunity
• Antibiotics cannot kill viral pathogens.
• Painkillers and other medicines are used to treat the symptoms of disease but do not kill pathogens. It is difficult to develop drugs that kill viruses without also damaging the body’s tissues.
• The heart drug digitalis originates from foxgloves.
• The painkiller aspirin originates from willow
• Penicillin was discovered by Alexander Fleming from the Penicillium mould