Marinas AaB in the human gene The location and relative size

Marinas AaB in the human gene The location and relative sizes of r are shown by the blue and red -ra r w rectangles, with alternative exons in (B) Splicing patterns for four tropomyosin mRNAs splicing ndicated by li connecting the esent that are in in the mRNA

Solution

The most accurate statement is

Exons 2 and 3 must each contain an integral number of codon ( that is, the number of nucleotides divided by 3 must be an interger).

The reason behind this correct statement is that, exons 2 and 3 are used in mRNAs, like exon 7 and 8 it means exon 2 and 3 can produce the same number of amino acid sequece as exon 7 and 8. So, if exon 2 and 3 can produce some definite amount of amino acids, then they must have an integaral number of codon.