Compare types of viral reproductive cycles

Question

Compare types of viral reproductive cycles

Answer 1

Lytic cycle:host cell is killed

      

Lysogenic cycle:virus genome isintegrated intohost genome(lysogeny)

      

Cell transformation:during integrated portion of lysogenic cycle, virus genes areexpressed in host cell;often involved in humandiseases (e.g. cholera)

Answer 2

Lytic Cycle stages:

1. Adsorption - the virus attaches to the outside of the cell

2. Insertion - the virus inserts its genes into the cell

3. Replication - the viral genes are replicated

4. Synthesis - the viral genes are read and viral proteins made by the cell's machinery

5. Assembly - the new viruses are assembled

6. Lysis - the host cell is burst as the new viruses are released

Lysogenic Cycle - the stages are essentially the same except that between 2 (Insertion) and 3 (Replication) is a stage where the viral genes are actually incorporated into the host DNA.  Then, the host cell goes on its business and each time it divides, the new cells get the viral DNA as well.  Then, when conditions are right, the viral DNA becomes activated and continues on with the process.  Some lysogenic viruses can remain dormant for years before actually become virulent.