Structure and Organisation of Nucleic Acids - DNA Review

A set of flashcards covering key vocabulary and concepts related to the structure and organization of nucleic acids, specifically DNA.

Deoxyribonucleic Acid (DNA)

A long polymer of repeating subunits, known as nucleotides, which includes a 5 carbon sugar (deoxyribose), a phosphate group, and nitrogenous bases.

Ribonucleic Acid (RNA)

A long polymer similar to DNA but contains ribose sugar and uracil instead of thymine.

Nucleotide

The individual subunit of nucleic acids, composed of a 5 carbon sugar, a nitrogenous base, and a phosphate group.

Phosphodiester bond

The bond formed between the phosphate group of one nucleotide and the 3'-OH group of another, linking nucleotides in a nucleic acid chain.

Chargaff's Rules

In DNA, the amounts of adenine (A) equals thymine (T) and the amounts of guanine (G) equals cytosine (C); also, G + A = T + C.

Watson-Crick base pairing

The specific pairing between adenine and thymine (A:T) and between guanine and cytosine (G:C) that stabilizes the DNA structure.

Primary Structure of DNA

The sequence of nucleotides in a DNA strand, determining its genetic information.

Secondary Structure of DNA

The double helical shape formed by the coiling of the DNA strand, held together by hydrogen bonds between base pairs.

Tertiary Structure of DNA

The higher-order folding and supercoiling of the DNA double helix.

Supercoiling

The over- or under-winding of a DNA strand, which can affect its functional properties and accessibility.

Hydrogen Bond

A weak bond that forms between the bases of complementary nucleotides; essential for the stability of the DNA structure.

Reannealing

The process by which denatured DNA strands reconnect and reform a double helix.

G-quadruplex

A non-B DNA structure formed by sequences rich in guanine, stabilizing by forming tetrads.

Triplex DNA

A structure where a single strand of DNA binds to a double-stranded DNA, creating a three-stranded helix.

Cot Curve

A graphical representation reflecting the rate of reassociation of nucleic acid strands, related to sequence complexity in the genome.

Major Groove

The larger of the two grooves in the DNA double helix where proteins typically bind, allowing access to the base pairs.

Denaturation

The process of separating double-stranded DNA into single strands by breaking the hydrogen bonds, often induced by heat.