Question

3) Use the logarithmic phase of the growth curve to estimate the generation time (g units are hours/generation; also known as the doubling time) of E. coli. How does the generation time that you estimated compare to the published generation times for E. coli growing under optimal conditions? What are some of the possible reasons for differences in the generation times? What are possible sources of error in this exercise?

Answer 1

Ans:

The difference in the times of generation may be due the following reasons

1. Presence of different amount carbon in the medium.

2. The presence of endospore.

3. Difference in pH of the medium.

4. Variation in incubation temperature.

5. Sampling time.

6. Quality and condition of inoculation of E.coli.

Possible source of error in this experiment are as follows;

1. Temperature error.

2. Error in the preparation of culture media.

3. Sampling error.

4. Error in bacterial isolation.

5. Calculation error.

6. Environmental variation.