Structure of DNA and RNA

Why are DNA and RNA called nucleic acids

They are weak acids

DNA is made up of

Two polymer chains known as polynucleotides
The chains are linked by hydrogen bonds between the bases of each polynucleotide chain

The chains are said to be

Antiparallel because they are oriented in opposite direction
Along each chain the nucleotides are bonded by phosphodiester bonds between the phosphate group of one monomer and the deoxyribose sugar of the adjacent monomer

RNA

Nucleic acid like DNA but four differences

RNA has single ribose sugar instead of deoxyribose

RNA has the base uracil instead of thymine

RNA is usually single stranded but can fold into 3d structures like proteins
RNA is usually shorter than DNA

The 5th carbon has

An attached phosphate group while the 3rd carbon has a hydroxyl group

When nucleotides are organised into the double strands of a DNA molecule

One strand runs in the 5th to 3rd direction while the other runs in the opposite way 3rd to 5th

The two strands are said to be antiparallel

DNA and RNA

Both are polymers of nucleotides

Nucleotides have three components phosphate pentose sugar and organic base

DNA contains a pentose called deoxyribose whilst RNA contains ribose

DNA bases

Adenine cytosine guanine and thymine

RNA bases

Adenine cytosine guanine an

In both DNA and RNA

Nucleotides join up to form a polymer by forming a covalent bond between the phosphate group of one nucleotide and the pentose of next (both called polynucleotides)

Double helix

Two strands are held together by hydrogen bonds between the nitrogen containing bases

RNA

Makes up the structure of ribosomes along with protein

RNA is made from a DNA template, so RNA is found in both the nucleus and cytoplasm of eukaryotic cells