There are a number of conserved sequences found in an mRNA which dictate where splicing occurs. Where are these sequences found relative to the exon/intron junctions? What is the significance of these sequences in the splicing process? One of these important regions is the branch point A found in the intron. What is the role of the branch pmnt A in the splicing process, and can this be accomplished with the OH group on either the 2' or the 3' carbon?