The 3'-5' phosphodiester linkages inside a polynucleotide chain serve to join

Question

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Answer 1

A strand of DNA or RNA consists of nucleotides linked together by phosphodiester bonds.
A phosphodiester bond exists between the phosphate of one nucleotide and the sugar 3' carbon of the next nucleotide.
This forms a backbone of alternating sugar and phosphate molecules known as the sugar-phosphate backbone.
The two strands of DNA are also antiparallel (run in opposite directions) to one another. A strand of DNA can have direction 5'-3' or 3'- 5'.
One strand of the DNA molecule is 5'-3' and the other strand is 3'-5'. A DNA strand is assigned direction based on what is found at the end of the strands.
The end of the strand with a free phosphate is the 5' end because phosphate attaches to the 5' carbon of the sugar.
The end with a free OH group is the 3' end because the OH group is attached to the 3' carbon of the sugar.
So, the correct answer is option D.

Answer 2

A strand of DNA or RNA consists of nucleotides linked together by phosphodiester bonds.
A phosphodiester bond exists between the phosphate of one nucleotide and the sugar 3' carbon of the next nucleotide.
This forms a backbone of alternating sugar and phosphate molecules known as the sugar-phosphate backbone.
The two strands of DNA are also antiparallel (run in opposite directions) to one another. A strand of DNA can have direction 5'-3' or 3'- 5'.
One strand of the DNA molecule is 5'-3' and the other strand is 3'-5'. A DNA strand is assigned direction based on what is found at the end of the strands.
The end of the strand with a free phosphate is the 5' end because phosphate attaches to the 5' carbon of the sugar.
The end with a free OH group is the 3' end because the OH group is attached to the 3' carbon of the sugar.

So, the correct answer is option D.