Final answer:
Bacteriophages are viruses that infect bacteria, with virulent phages undergoing the lytic cycle and temperate phages capable of both lytic and lysogenic cycles. Virulent phages lead to host cell lysis.
Step-by-step explanation:
Bacteriophages are viruses that infect bacterial cells, with two main types being identified: virulent phages and temperate phages. A virulent bacteriophage leads to the death of the host cell through the lytic cycle. During this process, the bacteriophage reproduces inside the cell and eventually causes cell lysis, releasing new virions. T-even phage is an example of a well-characterized class of virulent phages that exhibit this cycle.
In contrast, temperate bacteriophages can undertake both lytic and lysogenic cycles. During the lysogenic cycle, the phage DNA is incorporated into the host's genome, forming a prophage, which can be replicated with the host cell's DNA. This does not kill the host cell immediately. Over time, environmental stressors like starvation or exposure to toxic chemicals can trigger the prophage to begin the lytic cycle. The lambda virus is an example of a bacteriophage that follows the lysogenic cycle.
Understanding the life cycle of bacteriophages, including the lytic and lysogenic cycles, is essential since it serves as a model for understanding virus-host interactions and can inform therapeutic approaches such as phage therapy to target specific bacterial infections.