Nucleic acids

Question 1

Double helix

Answer 1

Shape of DNA molecule, due to coiling of the two sugar-phosphate backbone strands into a right-handed spiral configuration.

Question 2

Monomer

Answer 2

Molecule that when repeated makes up a polymer. Amino acids are the monomers of proteins. Nucleotides are the monomers of nucleus acids.

Question 3

Nucleotides

Answer 3

Molecule consisting of a five-carbon sugar, a phosphate group and a nitrogenous base.

Question 4

Polynucleotide

Answer 4

Large molecule containing many nucleotides.

Question 5

DNA polymerase

Answer 5

Enzyme that catalyses formation of DNA from activated deoxyribose nucleotides, using single stranded DNA as a template.

Question 6

Helicase

Answer 6

Enzyme that catalyses the breaking of hydrogen bonds between nitrogenous pairs of bases in a DNA molecule.

Question 7

Semi-conservative replication

Answer 7

How DNA replicates, resulting in two new molecules, each of which contains one old stand and one new strand of DNA. One old strand is conserved in each new molecule.

Question 8

Gene

Answer 8

A length of DNA that codes for a polypeptide or for a length of RNA that is involved in regulating gene expression.

Question 9

Polypeptide

Answer 9

A polymer made of many amino acid units joined together by peptide bonds.

Question 10

Protein

Answer 10

A large polypeptide of 100 or more amino acids.

Question 11

Transcription

Answer 11

The process of making messenger RNA from a DNA template.

Question 12

Translation

Answer 12

Formation of a protein, at ribosomes, by assembling amino acids into a particular sequence according to the coded instructions carried from DNA to the ribosomes by mRNA.