I'm doing this as a science project thats due tomorrow!!!! And... umm I swabbed areas of my house for bacteria to see which area had the most bacteria. I swabbed for samples Saturday, it is now Thursday. There are no signs of growth in the petri dishes. So... either I have a really clean house or I did something wrong.
2007-02-15 10:50:50 · 5 answers · asked by keenamonkey 3 in Science & Mathematics ➔ Biology
You might not have rubbed the swabs onto the dish properly, or you may not have rubbed them on the surfaces of your house enough. Maybe it hasn't been long enough for something to grow, there are certain environments bacteria need to be in, in order to grow. Or someone is playing a mean joke and switched your petri dish with an empty one.That's all I can think of. Good Luck! = )
2007-02-15 10:54:44 · answer #1 · answered by Miss*Curious 5 · 0⤊ 0⤋
I once did a science project like this but it took my dishes about a month to grow enough to be identified probably around 2 weeks to grow enough to see. The problem is that some bacteria won't grow in a petri dish and sometimes they only grow and multiply at a certain temperature that is higher then room temperature. For that you would need an incubator to make it moist and hot. That would get you results in probably 2 days. You can call a lab and ask them if you can use theirs if you know someone that does that kind of thing. If not i'm sure you can find someway to create and incubator on the web.
Oh , so the answer is that you didn't do your swabs enough ahead of time.
2007-02-15 11:03:28 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Did you employ Agar? if no longer, be particular you employ it. and do not placed water on your cotton swab that you're swabbing surfaces with... theres no want, basically more beneficial moisture. also, the aspect which has the most moisture must be placed flat on whichever floor you're laying it down on, so it would not drip on on your bacteria. also, putting the petri dish into an incubator will % up the technique fairly lots too.. attempt that, if it would not paintings you need to have done some thing incorrect.
2016-12-04 05:43:15 · answer #3 · answered by ? 4 · 0⤊ 0⤋
There may be several things keeping your microbes from growing. What type of media are you using? Many formulations of agar are selective, meaning they provide the nutrients that can be used only by certain bacteria.
What type of water are you using? Tap water contains impurities that may inhibit bacterial growth. Try again with distilled water.
How are you cleaning you petri dishes and your work implements? If you are using antibacterial soap, the triclosan is persistent on surfaces and will keep bacteria from growing (that's where the antibacterial part comes in.)
2007-02-15 16:54:28 · answer #4 · answered by datamonkey0031 2 · 0⤊ 0⤋
In order to get your bacteria to grow that fast, you would have to incubate the petri dishes- they mulitply best in higher temperatures.
2007-02-15 11:34:33 · answer #5 · answered by Dead Robin 2 · 0⤊ 0⤋