Question

The significance of checkpoints can be demonstrated by considering what happens when they are impaired.What would occur if there was a gain-of-function mutation in the promoter for the cyclin E gene such that cyclin E protein was always made at high levels even under conditions in which cyclin E would not normally be made?A) Cells will pass through the G2/M checkpoint with damaged DNA.B) Cells will pass through the G1/S checkpoint even if conditions are not ideal for cell division.C) Cells will pass the M checkpoint with chromosomes unattached to spindles.D) Cells will skip the S phase and go directly to G2 phase and not complete DNA replication.

Answer 1

Answer:

B) Cells will pass through the G1/S checkpoint even if conditions are not ideal for cell division.

Explanation:

The cells will pass through the G1/S checkpoint even if conditions are not ideal for cell division. Because cyclin E is an activator of CdK 2 which stimulates functions of cell entry into S phase.

The most important regulators of Cdk are called cyclin proteins. Cyclines are a family of proteins involved in cell cycle regulation. Cyclines form complexes with cyclin-dependent kinase enzymes (Cdks), activating their kinase function in the latter.

Hope this helps!