Science Buddies: "Ask an Expert"

hello, I'm doing a science project for school and finishing up my research. I'm growing bacteria in 2 Petri dishes. Petri dish #1 will be at a cool environment and Petri dish #2 will be at a warm environment to see which one grows the most. I need to know what temperature bacteria forms in and which place each dish grows bacteria successfully?

Hi Luna,

It would help if you would provide a little more information about the bacteria you are intending to use. Different bacteria have different ideal temperatures for growth. Many types of bacteria, including E. coli and S. aureus to name two relatively common organisms, grow best at 37 degrees Celsius (98.6 degrees Fahrenheit), which is human body temperature. Other types of bacteria will grow better at other temperatures. Generally when growing bacteria in the lab, we use an incubator to control the temperature. It's possible you may have access to an incubator in your school, but if not, they are relatively easy to build at home. Here are some links with suggestions:
https://www.sciencebuddies.org/science- ... php?t=7571
http://www.madsci.org/posts/archives/ma ... .Mi.r.html
https://www.sciencebuddies.org/science- ... ubator.pdf

I hope this help!
JMP

Thanks, I have one more question, I need to know what type of bacteria that are found on everyday objects. Example: door handles, keyboards, tables, remote controls and etc.

Hi Luna,

You can easily answer your own question--just google 'what type of bacteria are found on everyday objects'

You'll get lots of hits. For example:
http://www.inscribd.com/the-most-danger ... z2q8vAFh3v
which tells you about Escherichia ('E.') coli, Staphylococcus aureus, Salmonella and other baddies that hang out on our keyboards and the arms of chairs.

These bacteria are human pathogens, so you would have to grow them at 37C. As JMP suggested, you can easily build an incubator from a box with an incandescent light inside and a thermometer to read the temperature. Be careful! These bacteria can be dangerous.

Best wishes,
Sybee

Thank You very much!