Video Segment |04:05

Video Segment |04:05

Investigates the human immune system and how it fights off infectious diseases. The immune system, composed of organs, tissues, and cells, is the body’s defense system. It is composed of two main parts which are called the innate and adaptive immune systems. The innate system attacks germs, otherwise known as pathogens, and the adaptive system helps the body develop immunity. White blood cells can recognize pathogens using receptors. They also remember the pathogens and make the body immune to future attacks. When the immune system attacks diseases it sometimes causes the body to develop a range of symptoms including fever and inflammation. Vaccinations teach the immune system to fight certain infections that it has difficulty adapting to on its own.

©2017 Mazzarella Educational Media| CC| Grade(s)

Related Topics

  • adaptive immune system
  • B-cells
  • bacteria
  • blood
  • cells
  • fever
  • fungi
  • germs
  • immune system
  • immunity
  • infection

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