BIOLOGY
PROTEINS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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complementary copy of DNA
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an exact copy of DNA
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What genes are made of
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what brings amino acids to the ribosome
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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: -mRNA → DNA mRNA is a complementary copy of a DNA segment (gene) and consequently can be used to deduce the gene sequence. For converting a sequence from mRNA to the original DNA code, apply the rules of complementary base pairing: Cytosine (C) is replaced with Guanine (G) – and vice versa.
Detailed explanation-3: -The coding strand for a gene may be located in either strand of a given chromosome, 5’ to 3’ strand or 3’ to 5’ strand. An mRNA strand cannot be complementary to mRNA strand itself. Thus, the correct answer is C.