Question

Which of the following events might trigger induction of a temperate bacteriophage?

ANSWER:
1) Normal cell division of an infected cell
2) Bacterial conjugation
3) An infected cell entering the logarithmic phase of growth
4) Exposure to UV light

Answer 1

Exposure to environmental stressors such as UV light can trigger a temperate bacteriophage to switch from the lysogenic to the lytic cycle, leading to the destruction of the infected bacterial cell. The correct option is 4.

Step-by-step explanation:

The event that might trigger induction of a temperate bacteriophage from the lysogenic to the lytic cycle includes exposure to environmental stressors such as starvation or exposure to toxic chemicals like UV light.

For example, exposure to UV light can damage the bacterial DNA, which may induce the prophage to excise from the bacterial chromosome and enter the lytic cycle, leading to the production of new phage particles and subsequent lysis of the host cell.

During the lysogenic cycle of a temperate bacteriophage, the phage DNA gets incorporated into the host genome, becoming a prophage. This prophage is then passed on to subsequent generations of bacteria during normal cell division.

However, environmental stressors can induce the prophage to become active again, leading to cell lysis, which is characteristic of the lytic cycle.The correct option is 4.