Nucleic Acids

nucleotide

A molecule made up of a phosphate group and a nitrogenous base bonded to a 5-carbon sugar.

nucleic acid

A molecule made up of nucleotides linked to form a chain or strand

phosphodiester bond

Covalent bonds between the phosphate group on the 5′ carbon of one nucleotide and the -OH group on the 3′ carbon of a second nucleotide

complementary base pairing

Hydrogen bonding between A-T or A-U and G-C pairs in a nucleic acid

primary structure

 The sequence of nucleotides in a nucleic acid, read 5′ to 3′

secondary structure

Formation of a double helix in DNA or a stem-and-loop structure in RNA, based on complementary base pairing

sugar-phosphate backbone

The "spine" of 5-carbon sugars and phosphate groups in a nucleic acid (the nitrogenous bases project from this backbone).

antiparallel strands

Strands of DNA or RNA that align in opposite 5′ to 3′ orientation

monomer

A small "subunit" molecule that can be linked to another, via a covalent bond, to form a larger molecule called a polymer

polymer

A large molecule made up of strings of covalently bonded small molecules (monomers).