Students' Assignment:

1. Discuss the effects of lytic and lysogenic infections on the life cycle of the host
2. Discuss the factors responsible for the transformation of a lysogenic infection to one that is lytic
3. Distinguish between the replicative and maturation stages of a lytic phage infection
4. In this experimental procedure, why is it important to use a hard agar with a soft agar over-lay technique to demonstrate plaque formation?
5. Explain what is meant by plaque forming units
6. Determine the number of PFUs per ml in a 10-9 dilution of a phage culture that shows 204 PFUs in the agar lawn
7. The release of phage particles from the host bacterium always occur by lysis of the cell and results in the death of the host. Animal viruses are released by either the lysis of the host cell or exocytosis. Regardless of the mechanism of release, the animal host cell always dies. Explain.