🦠microbiology review

Plaques

Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025

Definition

Plaques are clear zones formed in a cell culture by the lysis of cells due to viral infection. They are used as an indicator of viral presence and activity.

Course connection

Topic 20.2: 20.2 Detecting Antigen-Antibody Complexes

Unit 20

5 Must Know Facts For Your Next Test

  1. Plaques result from the destruction of host cells by viruses, leading to visible clearings on a culture plate.
  2. The number of plaques can be used to quantify the amount of virus present in a sample.
  3. Plaque assays are commonly employed in virology to measure virus concentration and determine viral titers.
  4. Each plaque originates from a single infectious viral particle, making them useful for isolating pure virus strains.
  5. Plaque formation can be influenced by factors such as cell type, viral strain, and incubation conditions.