THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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3’
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5’
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3’
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5’
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Detailed explanation-1: -Which way’s which? When we look at a sequence of DNA, we read it in the 5′-3′ direction. The relative positions of genes or other sites along a DNA strand can be described as upstream (towards the 5′ end) or downstream (towards the 3′ end).
Detailed explanation-2: -DNA is always synthesized in the 5’-to-3’ direction, meaning that nucleotides are added only to the 3’ end of the growing strand. As shown in Figure 2, the 5’-phosphate group of the new nucleotide binds to the 3’-OH group of the last nucleotide of the growing strand.
Detailed explanation-3: -Once RNA polymerase and its related transcription factors are in place, the single-stranded DNA is exposed and ready for transcription. At this point, RNA polymerase begins moving down the DNA template strand in the 3’ to 5’ direction, and as it does so, it strings together complementary nucleotides.
Detailed explanation-4: -They help in the formation of mRNA. The coding strand is directed in the 3’ to 5’ direction. The template strand is directed in the 5’ to 3’ direction. The coding strand has a complementary nucleotide sequence.