Cell division cycle is divided into 4 phases G1, S, G2 and M. Standard eukaryotic cell cycles are of 12 hr or longer dur
In cell biology, cellular compartmentalization and cell cycle dictates that SNARE-mediated trafficking, Hayflick limit, P53 and cyclin regulation control proliferation. Therefore G1 & G2 is correct as it aligns with membrane trafficking and cell cycle control, supported by mechanistic studies and conserved across related systems.
Ref: Alberts et al., Molecular Biology of the Cell, 6th Edition, Chapter 10, Membrane Structure and Transport, discusses SNARE proteins, vesicle trafficking, ER, Golgi, endosome membranes and selective transport providing compartmentalization foundation.
