B1.2 - Key Words

Active site

Active site

Region of enzyme where substrate binds

Chromosome

Strand of DNA containing genes

Denature

Shape of an enzyme is changed so that it can no longer catalyse a reaction

DNA

Biological polymer made from nucleotide monomers. The sequence contains all the information needed to make an organism

DNA base

Nitrogenous base found in DNA - adenine, thymine, cytosine or guanine

Enzyme

Biological catalyst - this means it speeds up reactions without being used up

Gene

Section of DNA which codes for a characteristic

Lock and key hypothesis

Model that explains the specificity of enzymes

Nucleotides

Monomer (unit) found in DNA, consisting of an organic base, ribose sugar and a phosphate group

Polymer

Substance made up of many monomers (similar subunits) bonded together

Substrate

Molecules that an enzyme acts upon