Kerboodle 4 Flashcards
a The cleft on an enzyme molecule to which the substrate temporarily binds.
Active site ü
a The cleft on an enzyme molecule to which the substrate temporarily binds. c
Induced fit hypothesis ü
A substance additional to the enzyme and substrate that is also needed for the reaction to occur.
Cofactor ü
d A substance that binds to an allosteric site on an enzyme and impairs its function.
Non-competitive ü Inhibitor ü
e Regulation of a metabolic pathway that occurs when the last substance made negatively affects an enzyme at an early stage in the process.
(End) product inhibition ü
explain why
i the rate of amylase action is found by measuring substrate disappearance.
Substrate is starch ü Presence / concentration, can be shown with iodine solution ü
explain why ii the rate of catalase action is found by measuring product build-up.
Product is oxygen (gas) ü Can be collected, under water / in a gas syringe and volume measured ü
A series of experiments to measure the effect of different temperatures on the rate of a reaction was carried out. In each case, the volume of enzyme used was much smaller than the volume of substrate. Explain the reason for this.
Enzyme, is not used up / keeps working ü Substrate is used up and without it reaction stops ü
b Explain with reference to an example how competitive inhibitors can be used to treat people suffering from bacterial infections.
Example, Penicillin / other named β-lactam antibiotic / sulphonamides ü Inhibit enzymes that bacteria have but humans do not ü (Named) drug / inhibitor, binds to active site of enzyme preventing entry of correct substrate ü
Stage 1 milk is heated to 72 °C for 15 seconds (pasteurisation) i List two benefits of stage 1.
Microbes / bacteria, killed ü Enzymes denatured ü Stops spoilage reactions / people catching bacterial diseases or getting food poisoning ü
