Chapter 6 Define virus, viroid, virion, prion, provirus, reverse transcriptase, bacteriophage, and plaque. List four unique characteristics of viruses. Describe the structure of a naked virus and an enveloped virus. Describe three morphological groups of viruses. Discuss viral replication and contrast replication in naked viruses, enveloped viruses, and bacteriophage. Distinguish between lytic and lysogenic (temperate) bacteriophage. Describe two methods for the cultivation of animal viruses. Define and give examples of viral cytopathic effects Define oncogenic virus, latent viral infection, and lysogenic conversion..