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A bacterial culture is growing exponentially. At 7:00 AM, the number of cells was estimated to be 5.5 X 104 cells. At 11:00 AM, the number of cells increased to 8.7 X 107 cells. What is the generation time in minutes of the bacteria? Please assume we are in the log phase of growth for this bacterial population. Please show your work.

1 Answer

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To find the generation time, we need to use the formula:

N = N0 x 2^(t/g)

where:
N0 = initial number of cells
N = final number of cells
t = time elapsed
g = generation time

We can use the information given to solve for g.

At 7:00 AM, N0 = 5.5 x 10^4 cells
At 11:00 AM, N = 8.7 x 10^7 cells
The time elapsed is 4 hours, or 240 minutes.

Substituting these values into the formula, we get:

8.7 x 10^7 = 5.5 x 10^4 x 2^(240/g)

Dividing both sides by 5.5 x 10^4, we get:

1582.7 = 2^(240/g)

Taking the logarithm of both sides (base 2), we get:

log2(1582.7) = 240/g

Solving for g, we get:

g = 240 / log2(1582.7)

Using a calculator, we find that g is approximately 29.3 minutes. Therefore, the generation time of the bacteria is approximately 29.3 minutes.
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