Final answer:
Exponential growth is best seen in bacteria, where the population growth rate increases exponentially with time. In a large flask with unlimited nutrients, the number of bacteria doubles every hour through prokaryotic fission. After 1 day and 24 cycles, the population can increase from 1000 to more than 16 billion.
Step-by-step explanation:
The best example of exponential growth is seen in bacteria. Bacteria reproduce by prokaryotic fission. This division takes about an hour for many bacterial species. If 1000 bacteria are placed in a large flask with an unlimited supply of nutrients (so the nutrients will not become depleted), after an hour, there is one round of division and each organism divides, resulting in 2000 organisms-an increase of 1000. In another hour, each of the 2000 organisms will double, producing 4000, an increase of 2000 organisms. After the third hour, there should be 8000 bacteria in the flask, an increase of 4000 organisms. The important concept of exponential growth is that the population growth rate the number of organisms added in each reproductive generation is accelerating; that is, it is increasing at a greater and greater rate. After 1 day and 24 of these cycles, the population would have increased from 1000 to more than 16 billion. When the population size, N, is plotted over time, a J-shaped growth curve is produced (Figure 36.9).