BI-1277
Effect of temperature and pH on enzymes
Biology · Secondary 4 · Hard · Effect of temperature and pH on enzymes
A student investigates the effect of temperature on the activity of a digestive enzyme that breaks down protein in the small intestine. At 37 °C, the rate of reaction is highest. At 60 °C, almost no product is formed.
Using the lock and key hypothesis, which statement best explains the low rate at 60 °C?
Using the lock and key hypothesis, which statement best explains the low rate at 60 °C?
- The enzyme’s active site changes shape so the protein substrate no longer fits properly.
- The enzyme has more kinetic energy so it collides with the substrate less often.
- The protein substrate is completely used up at 60 °C so no more product can form.
- The enzyme molecules become closer together and block each other’s active sites.
Sign in to check your answer and see the hint and the worked explanation. Free on PrepLab High.