The cDNA for a eukaryotic gene B is 900 nucleotide pairs long.A cDNA clone is used to isolate a genomic clone of gene B,and the gene is sequenced.From start to stop codon,the gene is found to be 1800 nucleotide pairs long.The most probable reason for the discrepancy is that:

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The most likely reason for the discrepancy between the cDNA and genomic sequence is the presence of introns in the gene. The cDNA clone, which was made using reverse transcription of the mRNA, only contains the exons of the gene, while the genomic clone includes both exons and introns. Therefore, the 900 nucleotide pairs missing from the cDNA clone likely represent introns present in the genomic clone.

The CDNA for a Eukaryotic Gene B Is 900 Nucleotide