Enzymes Flashcards
What is the function of an enzyme?
Enzymes work as biological catalysts by speeding up reactions or allowing them to occur in conditions they might not usually. They do this by lowering the activation energy required for the reaction to take place.
How does the enzyme’s structure allow it to carry out its function?
Each enzyme has a unique active site which fits with a specific substrate. Once a substrate-enzyme complex has formed, the active site changes shape to either break apart and form products, or form chemical bonds needed for the reaction.
Define “optimum conditions.”
Enzymes function at their best in peek conditions. Outside of these conditions, they carry out their function slower or not at all.
Explain the effect of enzyme inhibitors on enzyme activity (competitive/non-competitive).
When enzyme inhibitors are present, the rate of enzyme activity decreases. Competitive enzyme inhibitors bind to the active site, blocking substrate particles from binding to the enzyme AS and forming products. Non-competitive enzyme inhibitors bind to the active sites of specific enzymes, changing the shape of it. This prevents specific substrates from binding to the AS and making products, thus leaving the enzyme inactive and slowing rate of enzyme activity.
Explain the effect of temperature increase on enzyme activity.
As the temperature increases up to the optimum temperature, the rate of enzyme activity also increases as the substrate and enzyme particles have more kinetic energy (move faster to collide more frequently with sufficient force to overcome Ea). Above the optimum temperature, enzyme activity decreases until it eventually stops. This is because the heat causes the bonds of the active site to break, denaturing the enzyme.
Explain the effect of pH change on enzyme activity.
Individual enzymes perform optimally in different pHs. A pH which is too high or too low can change the bonds holding the active site, thus denaturing it. Enzyme activity therefore decreases as they are unable to engage in substrate binding to make reactions occur.
