BI-1341
Lock-and-key model
Biology · Secondary 4 · Hard · Lock-and-key model
Tomato farmers spray a solution containing an enzyme that breaks down pectin in cell walls, making the fruits softer. According to the lock and key hypothesis, which statement best describes how this enzyme acts on pectin?
- The enzyme changes shape randomly until it can bind to any molecule, including pectin.
- The enzyme’s active site is complementary to pectin, so only pectin fits and is broken down.
- The enzyme’s active site is the same shape as all carbohydrates, so it digests any of them.
- The enzyme permanently changes its active site after reacting with the first pectin molecule.
Sign in to check your answer and see the hint and the worked explanation. Free on PrepLab High.