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Virus Definition

A virus is a nonliving protective shell with genetic material inside of it. For example, COVID-19 is a virus that infects human respiratory system cells.

View Lesson on Bacteria & Viruses
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Bacteria & Viruses

Fun Facts

  • Viruses need host cells to reproduce and then burst out, infecting other cells.
  • Most viruses on Earth only infect and kill bacteria.
  • Viruses don't move on their own and don't eat anything.

Why Do We Need To Know About

Learning about viruses helps us know how they affect our health and why it’s important to stop them from spreading. Sayings like “You should stay home when you’re sick so you don’t give the germs to others” and “Washing your hands gets rid of germs that can make you sick” show why it’s good to keep clean and stay away from others when sick to stop viruses from spreading and making more people sick.

Also, scientists who study viruses work on finding ways to treat and prevent diseases, like the vaccines for COVID-19. By understanding how viruses multiply and infect people, they can make big advances in medicine. This helps in finding new ways to prevent and treat viral illnesses.

Frequently Asked Questions

How do you know if something is living or nonliving?
Living things must take in nutrients, have genetic material, and reproduce.
What is a common way that bacteria and viruses are spread?
Bacteria and viruses can spread easily by touching.
Where can you find bacteria?
You can find bacteria everywhere! They are in the soil, on your skin, inside your body, and even in your poop! Bacteria grow together and are most often found in groups, called colonies.
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