Question

You are preparing two sandwiches at 6:30 AM, one for yourself and the other for your roommate. You accidentally cough and introduce 10 bacteria into each sandwich.

A. How many bacteria will be present when you eat your sandwich at 12:30 pm? The sandwich was lying in your locker throughout this time. The generation time of the bacteria is 30 minutes at room temp and 3 hours at 4⁰C.

Time in first row #bacteria in second row

6:30am	7:30am	8:30am	9:30am	10:30am	11:30am	12:30pm
10

B. Will the bacteria grow infinitely in the sandwich? What factors could contribute to growth (or lack of growth) in the sandwich?

C. List three ways you could have avoided getting sick from eating the sandwich? (Not eating the sandwich is not an option)

D.Your roommate also ate her sandwich at 12:30 PM. How many bacterial will be present on her sandwich when she eats it? Her sandwich was stored in a refrigerator (4⁰C) throughout this time. The generation time of the bacteria is 30 minutes at room temperature and 3 hours at 4⁰C.

6:30am	7:30am	8:30am	9:30am	10:30am	11:30am	12:30pm
10