This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Which parts of cell cycle are fixed in durationa) GIb) G2c) Sd) M \nSelect and explain. \nA. c, B. d, C. bcd, D. ac', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The time taken for S, G2 and M phases are similar for most cell types, occupying about 6, 4 and 2 hours respectively whereas the duration of G1 shows considerable variation as short as 2 hours in rapidly dividing cells i.e., embryonic tissue or longer than 12 hours in some adult tissue.', 'role': 'assistant'}]