Question

In a laboratory bacterial cell culture that has been infected by a virus, plaques are areas in which __________.

1) bacterial cells are resistant to the virus and have not been infected.
2) there is no nutrient available for the bacteria to grow.
3) the virus has spread and left behind the remains of dead cells.
4) the virus has not yet spread to that area of cells.

Answer 1

In a bacterial cell culture infected by a virus, plaques are clear areas where the virus has caused the lysis of host cells, leaving behind remnants of dead cells.

Step-by-step explanation:

In a laboratory bacterial cell culture that has been infected by a virus, plaques are areas in which the virus has spread and left behind the remains of dead cells. This process is a result of the viral infection cycle where the virus enters a host cell, replicates, causing cell damage, and then is released when the host cell undergoes lysis, which kills the cell. The released viruses then infect neighboring cells, leading to the formation of a clear area called a plaque on the bacterial lawn. Each plaque thus originates from a single virus and represents an area where host bacterial cells have been lysed by the viral infection.