When a bacteriophage virus infects a host cell, sometimes it causes virus nucleic acid to fuse with the DNA of the host cell and become part of the genome of every cell. While this is happening the virus is spreading without making new viruses and without showing symptoms of infection. This is called the .

lysogenic

Explanation:

Phages can generate the lytic cycle or the lysogenic cycle, although very few are able to carry out both. If lysis is carried out, lysogeny cannot be carried out and vice versa. In the lytic cycle, phage host cells are lysed (destroyed) after replication and encapsulation of viral particles, so that new viruses are free to carry out a new infection.

On the contrary, in the lysogenic cycle there is no immediate lysis of the cell. The phage genome can be integrated into the chromosomal DNA of the host bacterium, replicating at the same time as the bacterium does, or it can remain stable in the form of a plasmid, independently replicating bacterial replication. In any case, the phage genome will be transmitted to the entire progeny of the originally infected bacteria. The phage is thus in a state of latency until the conditions of the environment are deteriorated: decrease of nutrients, increase of mutagenic agents, etc. At this time, endogenous phage or phage are activated and give rise to the lytic cycle that ends with cell lysis.