Catalysts

Move around and collide

The enzyme remains unchanged

They lower the activation energy

The substrate is held as the active site so the atoms groups are close enough to react and the R groups of the active site interact with the substrate, forming a temporary bond which puts a strain on the substrate

Metals and chemicals

Metabolic reactions

Enzymes are usually faster, enzymes aren’t used up and enzymes are specific to one reaction so no unwanted byproducts produced.

40 million molecules

Maximum rate of an enzyme-controlled reaction

The molecule the enzyme helps to react

Formed when substrate fits into the active site

Formed as the reaction takes place

Site in the tertiary structure of an enzyme where the substrate is bound

Formed by the reaction and released by the active site at the end of the reaction

The substrate fits into the active site because of their complimentary shape. The enzyme binds to the substrate and an enzyme-substrate complex is formed. The substrate reacts and an enzyme-product complex is formed. The products are released, leaving the enxyme unchanged and ready for the next reaction.

The active site changes shape and the enzyme complex forms and the intital interactions between the active site and substrate are weak. These weak interactions change the tertiary structure of the active site strengthening the binding and putting strain on the substrate. This weakens particular bonds in the substrate, lowering the activation energy for the reactions. These weak interactions bring substrates closer together and weaken the bonds within the substrates lowering the activation energy for the reaction

All reactions go through a transition state as the different chemical compounds react with each other and the formation of the transition determines the activation energy of the reaction