Question

In what phase will the cell halt in when Cdc25 is inhibited?

A) G1 Phase
B) S Phase
C) G2 Phase
D) M Phase

Answer 1

The cell will halt in the G2 Phase when Cdc25 is inhibited, as the G2 checkpoint prevents the cell from starting the M Phase if the DNA has not been fully replicated or if it is damaged.

Step-by-step explanation:

When Cdc25 is inhibited, the cell will halt in the G2 Phase.

The G2 checkpoint is critical in ensuring that all of the chromosomes have been replicated and that the replicated DNA is not damaged. If this checkpoint is inhibited, as would be the case if Cdc25 is inhibited, the cell cycle will be halted. This prevents the entry into the M Phase, which is composed of mitosis and cytokinesis.

Regarding other questions mentioned, penicillin would be most effective during the log phase where bacteria are actively dividing and building their cell walls. Blocking S-phase would result in DNA replication not occurring, and external forces have the greatest influence at the G1 checkpoint.