Question

During which checkpoint do cell proteins determine whether growth factors that stimulate cells to divide are present

Answer 1

I think this happens during g1 phase. The g1 phase, is the first of four phases of the cell cycle that takes place in the eukaryotic cell division. During this phase the cell synthesizes mRNA and proteins in preparation for subsequent steps leading to mitosis. G1 phase ends when the cells moves into the S phase of the interphase