The 3 ^' -hydroxyl group used to initiate DNA synthesis comes from A) a RNA primer. B) the magnesium ion. C) uracils, always. D) amino acids, always.

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Quizplus · Accepted Answer

The hydroxyl group used to initiate DNA synthesis comes from a RNA primer. The primer is usually composed of RNA and provides a free 3'-OH group for DNA polymerase to add nucleotides onto during replication. The magnesium ion helps to activate the polymerase enzyme, but is not involved in providing the hydroxyl group. Uracils and amino acids are not involved in providing the hydroxyl group.

The 3 ' -Hydroxyl Group Used to Initiate DNA Synthesis

The 3 ^' -Hydroxyl Group Used to Initiate DNA Synthesis