Generation time of E-coli is

(20 minute) (271- Ananthanarayan 8th, 30- Chakrahorthy 2nd)* Many bacteria reproduce by binary fission and the average time required for the population, or the biomass, to double is known as generation time or doubling time.GENERATION TIME* Lepra bacillus - 24 Days* Tuberculous bacillus - 20 hours* Coliform E.coli - 20 minute* Clostridium - 10 minute* Each bacterial colony in a solid medium consists of descendants of a single cell* An ordinary bacterium doubles every 20-30 minutes and by geometric progression in exponential phase of growth thus a single bacterium can theoretically give rise to 1021 progeny in 24 hours roughly a ton of dry weight of bacterial cells.