Final answer:
The spliceosome recognizes specific sequences at the 5' and 3' ends of introns to carry out splicing by removing introns and joining exons together in pre-mRNA.
Step-by-step explanation:
The spliceosome is a protein complex that is responsible for splicing pre-mRNA by removing introns and joining exons together. It does this by recognizing specific sequences at the 5' and 3' ends of the intron. The spliceosome consists of RNA molecules called small nuclear RNAs (snRNAs) and proteins.
When the spliceosome binds to the intron, it forms a catalytic site where the intron is cut at two specific points. This releases the intron and brings the exons together. Finally, the exons are ligated together to form a continuous mRNA with all its codons intact and ready for translation.
Overall, the spliceosome identifies the exon/intron boundaries of a pre-mRNA through the recognition of specific sequences and carries out splicing by cutting and joining the RNA molecules.