Genetic engineering techniques can be used when analyzing and manipulating DNA and RNA. Scientists used gel electrophoresis to study transcription of gene L and discovered that mRNA strands of three different lengths are consistently produced. What explanations best accounts for this experimental result?

the precursor messenger RNA (pre-mRNA) of the L gene underwent alternative splicing, thereby producing three different mRNAs that have different lengths

Explanation:

In eukaryotic organisms, transcription produces a precursor mRNA (pre-mRNA), which is a non-processed RNA sequence that contains both non-coding regions (i.e., introns) and coding regions (i.e., exons). Subsequently, this pre-mRNA is converted into a mature messenger RNA (mRNA) by a process known as 'alternative splicing', where introns are removed and exons and exons spliced together to form a contiguous coding sequence. During alternative splicing, differential combinations of exons can be produced from the same gene, producing different mRNAs with different lengths.