Site pages
Current course
Participants
General
18 February - 24 February
25 February - 3 March
4 March - 10 March
11 March - 17 March
18 March - 24 March
25 March - 31 March
1 April - 7 April
8 April - 14 April
15 April - 21 April
22 April - 28 April
2.5.2 Generation Time
Bacterial numbers increase exponentially. The population will double in number during a specific length of time. The time required for a cell to divide is called the generation time or doubling time. For example, a culture tube is inoculated with one bacterium that divides every 20 minutes. The population would be 2 after 20 min, 4 cells after 40 minutes and so on. The increase in population is always 2n where n is the number of generations. ∴ After 6 generations the number of cells will be: Population = 26 = 64 After 20 generations = 220 = 1,048,576 This can be expressed as Nt = N0 x 2n Nt = the population at time ‘t’ N0 = the initial number log Nt – log N0 n = number of generation in time ‘t’ n = ----------------------- log 2 |