Question

What is the generation time of a bacterial population that increases from 10,000 cells to 10,000,000 cells in four hours of growth?

(a) 24 minutes

(b) 30 minutes

(c) 34 minutes

(d) 60 minutes

The question was asked in an internship interview.

I would like to ask this question from Data Analysis topic in chapter Presentation and Analysis of Data of Bioprocess Engineering

Answer 1

Right option is (a) 24 minutes

The explanation is: The generation time is the time interval required for the cells (or population) to divide.

G (generation time) = (time, in minutes or hours)/n(number of generations)

G = t/n

t = time interval in hours or minutes

B = number of bacteria at the beginning of a time interval

b = number of bacteria at the end of the time interval

n = number of generations (number of times the cell population doubles during the time interval)

b = B x 2^n (This equation is an expression of growth by binary fission)

Solve for n:

Logb = logB + nlog2

n = \(\frac{log_b – log_B}{log2}\)

n = \(\frac{log_b – log_B}{.301}\)

n = 3.3 logb/B

G = t/n