A bacterial culture has an initial cell count of 1000 cells/mL. If the bacterium has a doubling time of 20 minutes, how many cells will be present in the culture after 2 hours of growth?

The doubling time of the bacterium is 20 minutes, which means that the number of cells will double every 20 minutes. To find out how many cells will be present in the culture after 2 hours of growth (120 minutes), we can use the formula:

N = N₀ x 2^(t/d)

where N₀ is the initial number of cells, t is the time of growth, d is the doubling time, and N is the final number of cells.

In this case, N₀ = 1000 cells/mL, t = 120 minutes, and d = 20 minutes. So, we have:

N = 1000 x 2^(120/20) = 1000 x 2^6 = 1000 x 64 = 64,000 cells/mL

Therefore, after 2 hours of growth, the bacterial culture will have 64,000 cells/mL.