Final answer:
blastn is a search tool used in bioinformatics to compare nucleotide sequences and find similar sequences in a database. It is used to identify similar sequences, determine gene function, and find evolutionary relationships.
Step-by-step explanation:
blastn is a search tool used in the field of bioinformatics to compare nucleotide sequences. It searches for similarities between a query sequence and other nucleotide sequences in a database. This tool is commonly used to identify similar sequences in different organisms, determine the function of a gene, or find evolutionary relationships.
For example, if you input the sequence 'ATGCACACGGAGGGAAAAAAGCCCGGGAGAG' into blastn, it will search for similar sequences in the chosen database, such as the GenBank database, and provide a list of hits that match with the query sequence.