Question

Generation time of a bacteria is $20$ minutes. If initially there were $50$ cells in the culture medium, then what will be the number of cells after $2$ hours?

• A. $2400$
• B. $3200$
• C. $3000$
• D. $2560$

Answer 1

The correct option is B $3200$

The time taken by the bacteria to double in number during a period of certain time is called the generation time. This varies from one organism to another. E.coli divides ones for every 20 minutes. So, the generation time of E.coli is 20 minutes.

If 50 cells were there in the culture, after 2 hours the E.coli would be 3200 in number i.e, it completed 6 generations in two hours.

Thus, the correct answer is option B.