Bacterial Genetics

Question 1

What are the phases of bacterial growth?

Answer 1

• Lag phase
• Log phase (or Exponential phase)
• Stationary phase
• Death (or Decline)

Question 2

Label and explain the following diagram:

Answer 2

The following graph represents the growth dynamics of bacteria and their phases of growth.

1. Lag phase: this is the initial stage of bacterial growth. It represents the time of adaptation of bacteria

2. Log phase (or Exponential phase): shows the replication (growth & division) of bacteria. It represent the time at which the cell numbers increase

3. Stationary phase: represents the time when bacteria stops growing/multiplying. It is usually denoting of nutrients that the bacteria requires, running out

4. Death (or Decline): this is when there is no more nutrients in the environment for the bacteria to use

Question 3

What is the generation time of Mycobacterium tuberculosis & Vibrio cholerae?

Answer 3

Mycobacterium tuberculosis: 24 hours

Vibrio cholerae: 10 minutes