Transcript What Is Bacteria?

Demetris Abernathy, Angelina Banks, Dominique Liddell, Marcus Walters
Research Question
Which everyday item will have more bacteria on
it?
Items such as:
 Computer Mice
 Elevator Button
 Cell Phones
 Book Bags
Hypothesis
If people use their everyday items
more than ten times a day, then
there will be more bacteria on
those items than lesser used
items.
Background Research
There are many types of bacteria.
Before the invention of DNA
sequencing technique, bacteria
was classified by shapes and
sizes, otherwise known as
Morphology.
Background Research cont.
Most of the bacteria
needs oxygen to grow.
It takes 20 to 30
minutes to reproduce.
The following chart
shows the reproduction
of one bacterium cell, if
none of the bacteria
would die over the time
span.
1 Hour........................8
3 Hours...................512
6 Hours...........2.62x105
9 Hours.......... 1.34x108
10 Hours….... 2.68x108
11 Hours........ 5.16x108
12 Hours……. 1.03x109
Procedure
 In order to test the different objects first, we had
to swab the items with a moist cotton swab.
 Then we transferred the sample to a agar plates.
 Next, we let the plates sit for two days at 68 ̊ F.
 Lastly, we counted the colonies of bacteria and
recorded the data.
Materials
1.Distilled Water
2.Cotton Swabs
3.Our Everyday Items
4.Agar Plates
5.Gloves
Materials Cont.
 Purses
 Book Bags
 Cell Phones
 TV Remote
 TV “ON” Button
 Elevator Button
 Computer Mice
 Public Restrooms Inside Door Handle
 Dorm Restrooms Inside Door Handle
Data
Colonies
Brown
Small
White
Yellow
Purse
1.4
5
2.6
2.8
Book Bag
3.7
113.3
2.3
7.7
Cell phone "OK"
Cell phone
Earpiece
0
0.29
0.5
0
0
1.24
0.14
1.24
Elevator Button
Public Restroom
Boys
Public Restroom
Girls
Dorm Restroom
Boy
Dorm Restroom
Girls
0
347
0
0
0
3
0
0
0
2
0
0
0.5
58.5
0
0.5
50
136
50.5
50
Computer Mice
0.75
18`
1.5
0
TV Remote
0
6
0
0
TV On Button
0
15
0
2
400
Number of Bacteria
350
300
250
200
150
100
50
0
Results
We discovered that our hypothesis was false.
The computer mice were used more than ten
times a day, but are used by the same people.
The restroom and elevator buttons did prove to
be true.
Conclusion
The dorm computers were used more
than ten times but did not have as much
bacteria on them because they are used
by the same people all the time. On the
other hand the elevator button and public
restrooms are not used by the same
people everyday and the people that use it
may not wash there hands.
Further Investigation
Some of our mistakes was that the agar plates
were not air tight. The air-borne bacteria leaked into
the plates and caused extra growth on the control
and some other plates that weren’t even used.
Work Cited
 LaRosa, Liz. "Where can we find bacteria?". 6/18/09
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<middleschoolscience.org>.
"Agar Plate". Wikipedia. 6/24/09
<http://en.wikipedia.org/wiki/Agar_plate>.
http://guccigoods.com/wpcontent/uploads/2008/03/authenticate_gucci_handbag.jpg
http://dontblinkjustthinktech.files.wordpress.com/2008/03/sprint-lgrumor.jpg
http://www.ict-science-tosociety.org/Pathogenomics/images/bacteria_cell.jpg
http://images.tigerdirect.com/skuimages/large/targus-TSB082US-T222315-ma.jpg
http://www.buzzle.com/articles/different-types-of-bacteria.html
Mrs. Morgan
Mrs. Scott
Ms. Bower
Ms. Daphne
Questions?