Processing, please wait...
It was processed successfully!
It was processed successfully!
Login Create Free Account
Create Free Account

Bacteria Definition

Bacteria are single-celled organisms that reproduce quickly, some causing diseases. For example, salmonella can result from undercooked food.

View Lesson on Bacteria & Viruses
Grades 6-8 VideoBacteria & Viruses player orange
Preview Only
Oops! It looks like your security settings are blocking this video 🙁

If you are on a school computer or network, ask your tech person to whitelist these URLs:
*.wistia.com, fast.wistia.com, fast.wistia.net, embedwistia-a.akamaihd.net

Sometimes a simple refresh solves this issue. If you need further help, contact us.


Bacteria & Viruses

Fun Facts

  • Bacteria cells can split every 20 minutes, rapidly increasing in number.
  • Cheese is made when bacteria break down milk.
  • Bacteria are found almost everywhere on Earth, including in the soil, on your skin, inside your body, and even in your poop!

Why Do We Need To Know About Bacteria

Learning about bacteria helps us see how important they are in everyday life and in many jobs. Bacteria help make foods like cheese, sauerkraut, and yogurt, which is cool for those interested in cooking and food science.

Bacteria are also used in medicine to create new antibiotics and in making biofuels for energy. This shows how knowing about bacteria can lead to careers in science, health, and more.  Bacteria are important to our world and jobs.

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.
Explore More Science Topics
We’ve sent you an email with instructions how to reset your password.
Choose Your Free Trial Period
3 Days

3 days to access to all of our teaching resources for free.

Continue to Lessons
30 Days

Get 30 days free by inviting other teachers to try it too.

Share with Teachers
Get 30 Days Free
By inviting 4 other teachers to try it too.
4 required

*only school emails accepted.

Skip, I will use a 3 day free trial

Thank You!

Enjoy your free 30 days trial