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If one end of a DNA strand has a phosphate group on it, the chemical group on the other end must be

A. phosphate.

B. carboxyl.

C. hydroxyl.

D. methyl.

User SuperMagic
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1 Answer

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Final answer:

The DNA strand with a phosphate group on one end will have a hydroxyl group on the other end, thus the correct answer is (C) hydroxyl.

Step-by-step explanation:

If one end of a DNA strand has a phosphate group on it, the chemical group on the other end must be a hydroxyl group. In DNA, nucleotides are linked together by phosphodiester bonds, forming a long polymer chain. The phosphate group of one nucleotide is covalently bonded to the 5' carbon of the sugar, and through a series of phosphodiester bonds, it connects to the hydroxyl group at the 3' carbon of the adjacent nucleotide. This forms the sugar-phosphate backbone that is characteristic of DNA, with a free phosphate group at the 5' end of the chain and a free hydroxyl group at the 3' end.

Consequently, if a DNA strand has a phosphate group at one end, the other end will be terminated with a hydroxyl group, making the correct answer to the question (C) hydroxyl.