The multiple choice questions have five answer choices — one (and only one) is correct in each case.
In the graph above, the time when the number of living bacteria is increasing at the greatest rate occurs
Select an Answer
during the first 2 hours
between the 2nd and the 4th hour
between the 4th and the 6th hour
between the 6th and the 10th hour
between the 11th and the 13th hour
The greatest rate of bacterial population growth occurs between 4 and 6 hours after inoculation. This question asks when the greatest rate of growth occurred, not when the number of bacteria was greatest. The curve is steepest between 4 and 6 hours after inoculation, making that the time period with the greatest rate of growth.