I am a beginner of cell culture experiments and just have started some experiments with Hela cell line.In research papers, it is always highlighted that, each experiment has been done in triplicate- what is the ideal meaning of that? Suppose, I want to check gene X expression pattern in my cell line.What is the true biological replicate in my cell culture experiment-
1) Revive three separate vials of cells in different times, culture them in different times, isolate RNA and make cDNA from those.
2) Revive just one vial of cells, isolate the RNA from 1st batch, keep on culturing, in the next passage further isolate RNA for 2nd time, 3rd passage again extract RNA for 3rd time.
I can not understand which procedure should I follow for my experiments ( RT-PCR, western etc.). Please help me.
Regards