Final answer:
The statement that lambda phage DNA always integrates into the same specific site in the host DNA is false. Environmental stress can cause the prophage to exit the genome and enter the lytic cycle, contradicting the idea of always integrating at the same site. Answer is false
Step-by-step explanation:
Answer is false The lambda phage DNA indeed has a very specific site where it integrates into the host genome during the lysogenic cycle. However, the statement "The lambda phage DNA always integrates into the host DNA in the same specific site" is false. Under certain conditions, such as environmental stress, the prophage (integrated phage DNA) can exit the host genome and re-enter the lytic cycle, where it will produce new phages and cause the lysis of the host cell. This process is known as specialized transduction, and it involves the transfer of specific pieces of bacterial chromosomal DNA near the site of integration by the phage.
In summary, the normal integration site for lambda phage DNA is specific, but the integration is not always irreversible. Environmental conditions can influence the phage life cycle, and determine whether the phage enters the lytic or the lysogenic cycle. During the lytic cycle, new phages are produced, and upon lysis, they are released into the environment. In contrast, the lysogenic cycle is characterized by the incorporation of phage DNA into the host genome, where it may remain dormant until conditions signal it to exit and begin the lytic cycle.