BiologyGuideCells & MoleculesDiseasesEcosystemHuman BiologyAQA BIOL1AQA HBIO1AQA HBIO2AQA HBIO4AQA HBIO5
Cell DivisionCell TypesCell UltrastructureEnzymesGene TechnologyGenes, DNA, RNALarge MoleculesPlasma MembraneRespiration
Video tutorials

Supplemental Videos

Click here to watch video tutorials for exam board specific videos by A* students

Enzymes

Changes in pH

Enzyme Conc. is proportional to rate of reaction, provided other conditions are constant. Straight line
Substrate Conc. is proportional to rate of reaction until there are more substrates than enzymes present. Curve becomes constant.

Increased Temperature

Decreased Temperature

Inhibitors

End-product inhibition

The metabolic pathway contains a series of individual chemical reactions that combine to perform one or more important functions. The product of one reaction in a pathway serves as the substrate for the following reaction.