Enzymes. Flashcards
(18 cards)
What is an extracellular enzyme?
An enzyme that works outside the cell.
What is an intracellular enzyme?
An enzyme that works inside the cell.
Name an intracellular enzyme.
- Catalase
Name extracellular enzymes.
- Trypsin
- Amylose
What determines the shape of the active site?
Tertiary bonds.
What is a prosthetic group?
A cofactor that is permanently bound, by covalent bonds, to an enzyme.
Give an examples of prosthetic groups.
- A zinc ion in carbonic anhydrase. (Zn2+)
- Haem prosthetic group in haemoglobin.
What is a cofactor?
A substance that has to be present to ensure that an enzyme-catalysed reaction takes place at an appropriate rate.
What is a coenzyme?
Small organic non-protein molecules that bind temporarily to the active site.
What is an example of a coenzyme?
- b12.
What are the two models of enzyme action?
- Lock-and-key.
- Induced fit.
Outline the mechanism of enzyme action.
What are the 4 factors that effect the rate of enzyme catalysed reactions?
- Temperature
- pH
- Substrate concentration
- Enzyme concentration.
Why are enzymes referred to as “biological catalysts” ?
How do enzymes impact the rate of reaction?
Enzymes lower the activation energy needed to active the reaction.
How do you calculate the Q10?
(rate of reaction at (x + 10) °C) ÷ (rate of reaction at x °C)
Where does a non-competitive inhibitor bind?
The allosteric site of the enzyme.
