Directions
Let’s take a look again at bacterial growth. There’s something exponential about it. Look at the red numbers along the curve. Do you see a pattern?
The graph shows that bacteria double every hour. So we multiply the number of cells by 2 for every hour that passes. This is a pattern called exponential growth.
For example, at 1 hour, we have 2 cells. At 2 hours, the cells have doubled, so now we have 2 × 2 = 4 cells. 2 × 2 is the same as 2². So we can say that at 2 hours there are 4, or 2² cells. The pattern continues: at 3 hours, we have 2³ cells, and so on as you see in the last row in the table below.
