The critical phase of cell cycle is S phase, in this phase the DNA starts replicating.The cell cycle is called the synthesis phase because the synthesis of DNA starts in this phase. There is no chance that the cell can go back to the previous phase. The DNA within the cell starts replicating. Depending upon the level of nutrients, energy and external factors, cells must decide that they will enter into cell cycle or not.
What are his observations? We can’t answer this without knowing his observations if those are the conclusions. Please provide the rest of the information and I can answer.
