Enzymes
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Preview questions (no answers)
- 1.
When an enzyme is denatured by extreme pH, which of the following occurs?
A.The enzyme's primary structure is completely broken into amino acids
B.The substrate changes its shape to match the new enzyme shape
C.The active site changes shape, preventing substrate binding
D.The enzyme works faster to compensate for the pH change
- 2.
What happens to the rate of an enzyme-controlled reaction as the temperature increases from to ?
A.The rate decreases because the enzyme becomes too active
B.The rate remains constant as enzymes are unaffected by temperature
C.The rate increases due to higher kinetic energy and more frequent collisions
D.The rate decreases as the substrate molecules move too fast to bind
- 3.
Based on the diagram of enzyme action, which letter represents the enzyme-substrate complex?
A.A
B.B
C.C
D.D
Download the worksheet for Enzymes - Enzyme action to practice offline. It includes additional chapter-level practice questions.
Effects of temperature and pH
SubtopicEffects of temperature and pH under Enzymes for Grade 12 IGCSE.
Preview questions (no answers)
- 1.
Which statement best describes the effect of pH on enzyme activity?
A.All enzymes work best at pH 7.
B.The rate of reaction increases indefinitely as pH increases.
C.Extremely high or low pH can lead to enzyme denaturation.
D.pH only affects the substrate, not the enzyme.
- 2.
In the human body, most enzymes have an optimum temperature closest to which value?
A.B.C.D. - 3.
Which of the following terms describes the specific pH at which an enzyme shows its highest level of activity?
A.Maximum pH
B.Equilibrium pH
C.Optimum pH
D.Neutral pH
Download the worksheet for Enzymes - Effects of temperature and pH to practice offline. It includes additional chapter-level practice questions.