AP BIOLOGY

Detailed explanation-1: -cDNA (short for copy DNA; also called complementary DNA) is synthetic DNA that has been transcribed from a specific mRNA through a reaction using the enzyme reverse transcriptase. While DNA is composed of both coding and non-coding sequences, cDNA contains only coding sequences.

Detailed explanation-2: -Complementary DNA (cDNA) is a DNA copy of a messenger RNA (mRNA) molecule produced by reverse transcriptase, a DNA polymerase that can use either DNA or RNA as a template.

Detailed explanation-3: -cDNA is created from a mature mRNA from a eukaryotic cell with the use of reverse transcriptase. In eukaryotes, a poly-(A) tail (consisting of a long sequence of adenine nucleotides) distinguishes mRNA from tRNA and rRNA and can therefore be used as a primer site for reverse transcription.

Detailed explanation-4: -mRNA is formed as a complementary strand to one of the two strands of the DNA. Three of the four nitrogenous bases that make up RNA-adenine (A), cytosine (C), and guanine (G)-are also found in DNA. In RNA, however, a base called uracil (U) replaces thymine (T) as the complementary nucleotide to adenine.

Detailed explanation-5: -4.22 Reverse Transcription Polymerase Chain Reaction. Reverse transcription polymerase chain reaction (RT-PCR) is used to make a complementary DNA (cDNA) from the extracted mRNA for finding the specific protein-coding gene or for our cell to acquire the protein encoded in the mRNA.