Question

the graph shows changes over time in a population of bacteria added to a test tube of growth medium. what activity characterizes the growth cycle during phase ii?
a bacteria are weakening due to the accumulation of waste products.
b bacteria are increasing in metabolic activity though not dividing.
c bacteria are dying off rapidly from lack of nutrients and space.
d bacteria are dividing regularly by binary fission.

Explanation:

• Phase I: Bacteria adjust to the environment, metabolic activity increases but no division (lag phase).
• Phase II: Bacteria divide regularly by binary fission (logarithmic or exponential growth phase).
• Phase III: Growth slows as nutrients deplete and waste accumulates (stationary phase).
• Phase IV: Bacteria die off rapidly (death phase).

Answer:

D. Bacteria are dividing regularly by binary fission.