| A | B |
| enzymes are made of | protein |
| active site | the area where a substrate fits |
| enzymes are specific | they will only work on 1 substrate |
| lock and key model | how enzymes and substrates fit together |
| denatured | when an active site has changed shape |
| the most important feature of an enzyme | shape |
| optimum | the temperature an enzyme works best at |
| increasing temperature | increases enzyme movement |
| increasing enzyme movement | increases the number of collisions |
| very high temperatures | cause denaturation |
| very low temperatures | cause few collisions |
| different enzymes | have different optimum temperatures |
| enzymes will only usually work best | at the optimum pH |
| most human enzymes | work best at body temperature |
| at low substrate concentrations | many enzymes have empty active sites |
| at high substrate concentrations | most active sites contain substrates |