why RPMI is used in chromosomal analysis?

Answer:
What does RPMI stand for in your question?The only "RPMI" I know of is a type of medium cells can be grown in. In this case, RPMI stands for "Roswell Park Memorial Institute", the place where the media was first developed.If this is the RPMI you mean, then it is used to grow cells in. The chromosomes would then be isolated from the cells for analysis. RPMI is a common medium, but there are literally thousands of other types of media (plural of medium) that many cells can grow in.

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Like the man already said, RPMI-1640 was developed by Moore et. al. at Roswell Park Memorial Institute, hence the acronym RPMI. There are about 10 or 12 versions of this medium, each modified for a particular usage. RPMI is a common medium in chromosomal studies including: routine, high resolution, hematologic malignancy, lymph node tissue and products of conception. If you really care what's in a particular medium and its uses, go to the Sigma-Aldrich site below and look around.

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