Nucleotides are joined by which linkages that form the backbone?

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Multiple Choice

Nucleotides are joined by which linkages that form the backbone?

The link that forms the backbone of nucleic acids is covalent phosphodiester bonds. These bonds connect the 5' phosphate group of one nucleotide to the 3' hydroxyl group of the next, creating a continuous sugar–phosphate chain that runs in the 5' to 3' direction. This backbone provides the molecule with stability and a defined shape, while the nitrogenous bases protrude to the interior and pair with their partners on the opposite strand via hydrogen bonds. Hydrogen bonds between bases are crucial for holding the two strands together, but they are not backbone linkages. Ionic bonds don’t link nucleotides in the backbone, and peptide bonds are what join amino acids in proteins, not nucleotides.

The link that forms the backbone of nucleic acids is covalent phosphodiester bonds. These bonds connect the 5' phosphate group of one nucleotide to the 3' hydroxyl group of the next, creating a continuous sugar–phosphate chain that runs in the 5' to 3' direction. This backbone provides the molecule with stability and a defined shape, while the nitrogenous bases protrude to the interior and pair with their partners on the opposite strand via hydrogen bonds.

Hydrogen bonds between bases are crucial for holding the two strands together, but they are not backbone linkages. Ionic bonds don’t link nucleotides in the backbone, and peptide bonds are what join amino acids in proteins, not nucleotides.

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