DNA Structure and Properties

Vocabulary flashcards covering the levels of DNA structure, base pairing rules, denaturation, and polymerase chain reaction (PCR).

Genes

Stretches of DNA that carry the codes for protein production.

Primary structure of DNA

The sequence of nucleotide residues, which can be represented by the base that is present.

Secondary structure of DNA

The double helix formed by two antiparallel DNA strands connected by complementary bases that are hydrogen bonded to each other.

Antiparallel strands

Strands in the DNA double helix that run in opposite directions, with one strand running from the five prime to three prime end and the other from the three prime to five prime end.

Sugar-phosphate backbone

The structure on the outside of DNA composed of the monosaccharide deoxyribose attached to phosphate, giving the exterior a negative charge.

Complementary bases

Specific pairs of nitrogenous bases on the inside of the double helix that hydrogen bond to each other, namely adenine to thymine and cytosine to guanine.

Adenine-thymine base pair

A complementary base pair connected to each other by two hydrogen bonds.

Cytosine-guanine base pair

A complementary base pair connected to each other by three hydrogen bonds.

Denaturation (of DNA)

The separation of the two strands of the double helix caused by the disruption of hydrogen bonds between complementary base pairs, which can be induced by heat.

Polymerase Chain Reaction (PCR)

A process using heat denaturation to duplicate or replicate a small sample of DNA in the laboratory into a larger sample for genetic analysis.