ADVERTISEMENT |  REMOVE ADS

What Types of Bacteria Are Found in Your House?

Bacterial organisms are everywhere. They are in our homes and schools, in our foods, and in the air we breathe. Your body is marvelously designed to fight bacteria when it enters your body through a cut or another means. While some bacteria is necessary in your body, too much, or the wrong types, can cause serious problems.

Bacteria are smaller than cells and often invade cells. If your body can't protect itself through its immune system, the bacteria will eventually destroy the cell.

One of the problems with bacteria is that you can't see it. If you could, you could do a better job of avoiding it. In the experiment described below, however, you get to not only collect bacteria, but see it grow, as well.

You'll collect samples of bacteria from different areas in your home, then allow it to grow in covered petri dishes containing the nutrient agar. Petri dishes are available from biological supply companies. A set of 10 dishes will cost you about $5. Be sure to label each dish carefully so you know from which area the bacteria inside of it was taken.

Some good areas within your home to check are door handles, the insides of your sneakers, door handles, bathroom taps, your teeth, and the computer's keyboard.

Use a cotton swab to wipe the surface you're testing, then wipe the swab gently onto the nutrient gel in the petri dish. Put the cover, also labelled, onto the petri dish and place it in a dark, warm area where the bacteria can grow undisturbed.

Check for bacterial growth every 12 hours for one week. Record any changes in each dish noting the amount, colour and shape of the bacteria.

At the end of a week you will be able to clearly see what areas in your home have the most bacteria. You can chart your information, providing helpful information for your parent or guardian.

Make sure you throw away the petri dishes at the end of the experiment. It would be a good idea to photograph each dish at the end of the experiment for your display at the science fair.

An interesting step further would be to test the back doorknob, then wipe it clean with bleach and swab it again and test for bacteria. This would help you to see if the cleaner did its job and killed the germs.

Excerpted from

The Complete Idiot's Guide to Science Fair Projects
The Complete Idiot's Guide to Science Fair Projects
Nancy O'Leary and Susan Shelly
This book contains great information for different kinds of science fair projects.


Introduce your students to different types of bacteria found in the household with this printable science activity. Students will monitor samples of bacteria and observe their growth over a period of time.
Grades
6 |
7 |
8 |
9
Subjects
Science (4,731)

Biology (1,753)


TYPE:
Lesson Plans (1,037)

Activities (2,882)

Join TeacherVision today

Spend more time teaching and less time searching.
Get full, ad-free access to all our learning resources—curated and vetted by teachers
and curriculum specialists—for one-low price.

Sign Up Sign Up

Go Premium

Get unlimited, ad-free access to all of TeacherVision's printables and resources for as low as $2.49 per month. We have a plan for every budget. 

Select a plan

All plans include a free trial and enjoy the same features. Cancel anytime.
Learn more about Premium