When doing a plaque assay with human or animal cells, a layer of nutrient media mixed with agar is put on top of the cells after they have been infected with the diluted virus.What is the major purpose of this agar layer?

Question

Quizplus · Accepted Answer

The major purpose of the agar layer is to limit the movement of virus particles, allowing for the formation of distinct plaque formations which can be counted and used to calculate viral titer. The other options (A, B, and C) are not correct as the cells are already growing in nutrient media before the agar layer is added, and the agar layer does not actively promote virus replication or make infected cells easier to visualize.

When Doing a Plaque Assay with Human or Animal Cells