Cell division, with the passage of time, the number of cells increases geometrically (exponential, such as the n power of a)

Suppose cells divide every second.

After the first second, the total number of cells changed from one to two (2 to the first power).

After the second time, the total number of cells changed from two to four (the square of two).

After three seconds, the total number of cells changed from four to eight (the third power of two).

......

After the nth second, the total number of cells becomes the n power of 2.