Explain how two nucleotides are linked in the same DNA chain that will lead to the DNA chain having the correct direction

Answer 1

In a DNA chain, nucleotides are linked through a phosphate group on the 5' carbon of one nucleotide and the hydroxyl group on the 3' carbon of the next nucleotide. This creates a phosphodiester bond between the nucleotides, forming the sugar-phosphate backbone of the DNA molecule.

The orientation of the nucleotides in the DNA chain is critical in determining the direction of the chain. The 5' end of the chain has an unbound phosphate group on the 5' carbon of the first nucleotide, while the 3' end has an unbound hydroxyl group on the 3' carbon of the last nucleotide.

Thus, in order to ensure that the DNA chain has the correct direction, the phosphate group of the next nucleotide must always be added to the 3' carbon of the previous nucleotide. This creates a directional polarity in the DNA chain, with the 5' end and 3' end at opposite ends of the chain.

Overall, the correct linkage of nucleotides through the phosphodiester bond and the proper orientation of the nucleotides in the DNA chain ensure that the chain has the correct direction, which is essential for proper DNA replication, transcription, and translation.