Question

$cDNA$ stands for

• A. circular DNA
• B. complementary DNA
• C. coiled DNA
• D. cytoplasmic DNA.

Answer 1

Answer: (B)

Complementary $DNA(cDNA)$ is a form of $DNA$ prepared by using $mRNA$ as template, i.e., the reverse of the usual process of transcription in cells. The synthesis is catalysed by reverse transcriptase. $cDNA$ thus has a base sequence that is complementary to that of the $mRNA$ template. Unlike genomic $DNA$ , it contains no noncoding sequences (introns). $cDNA$ is used in gene cloning for expressing eukaryotic genes in prokaryote host cells, or as a gene probe to locate particular base sequences in genomic $DNA$