Final answer:
The one-step growth curve for viruses involves three stages: inoculation, eclipse, and the critical burst phase, which leads to a steep rise in viral titer due to the mass release of new virions when host cells lyse. This burst is primarily responsible for the sharp increase seen in their growth curve, contrasting with the sigmoidal curve of bacterial growth.
Step-by-step explanation:
The subject of this question is the one-step growth curve for viruses, specifically bacteriophages. This process can be broken down into three phases: inoculation, eclipse, and burst. In the inoculation phase, virions attach to host cells. During the eclipse phase, the viral genome enters the host cells, but no virions are detected outside.
The most defining phase is the burst phase, where a significant increase in virus population occurs due to the sudden release of new virions from lysed host cells, contributing to the steep rise in viral titer. This phase corresponds to the sudden increase in the growth curve of a virus.
The stark increase in viral titer is attributed to the burst size, which is the maximum number of virions produced per bacterium. Unlike bacteria that show a sigmoidal growth curve, the growth curve of bacteriophage populations is represented by a one-step multiplication process. This leads to a very sharp rise in the number of viruses, unlike the gradual increase seen in bacterial cultures.