Immobilization reduces enzyme-substrate collisions

Steps:

• Immobilization fixes papain to beads, restricting its movement compared to free solution.
• Free papain diffuses rapidly, enabling more frequent collisions with substrate molecules.
• Restricted mobility in immobilized form limits diffusion paths, decreasing collision rates.
• Graph shows lower activity for immobilized papain across temperatures due to this kinetic barrier.

Why C is correct:

• Immobilization reduces enzyme mobility, lowering the frequency of productive collisions as per collision theory in enzyme kinetics.

Why the others are wrong:

• A: Immobilization typically stabilizes structure without altering curve shape; graph likely shows parallel shifts.
• B: It increases thermal stability, allowing higher temperature tolerance, not decreases.
• D: Identical to C but grammatically flawed; not a distinct incorrect option.

Final answer: C