Final answer:
Spliceosome recognition sequences are important for recognizing introns and splicing. They are located at each end of an intron and are marked by specific nucleotides, GU at the 5' end and AG at the 3' end of the intron.
Step-by-step explanation:
Introns are non-protein coding intervening sequences that are spliced from mRNA during processing. The recognition and removal of introns during splicing is facilitated by specific sequences called spliceosome recognition sequences. These recognition sequences are located at each end of an intron and are marked by specific nucleotides, GU at the 5' end and AG at the 3' end of the intron.