What would happen to and its offspring if the cells did not go through a g1 phase during their cell cycle

G1 is the most important phase of meiosis or mitosis.It is the phase when the first cell growth happens.If G1 never happens,the cell aren't mature and DNA chromosomes won't be condensed.The next phase,S phase,take the DNA and copies them.If the DNA never got condensed and mature in G1 phase,S phase wouldn't be accurately completed and then this could result in mutations,and etc.
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Both of them have a nucleus, golgi apparatus, cell membrane, smooth and rough endoplasmic reticulum, lysosome, and ribosomes.

Yes yes yes very good