B1.2 - Key Words

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