▶️ Answer/Explanation
Detailed solution
(a)
The results show that pH affects the activity of both enzymes, but they have different optimums.
- Trend: For both enzymes, activity increases to a peak and then decreases.
- Optimum pH: Enzyme \(\textbf{L}\) has an optimum pH of 2, with a maximum area digested of \(160~\text{mm}^2\). Enzyme \(\textbf{M}\) has an optimum pH of 10, with a peak activity of \(140~\text{mm}^2\).
- Activity Range: Enzyme \(\textbf{M}\) is active over a wider range (pH 3 to 12) compared to Enzyme \(\textbf{L}\) (pH 1 to 5). Enzyme \(\textbf{L}\) shows the steepest increase in activity between pH 1 and 2.
- Data Point: At pH 5, Enzyme \(\textbf{L}\) stops working (0 activity), whereas Enzyme \(\textbf{M}\) is active with an area of \(30~\text{mm}^2\).
(b)
At pH 2, the activity of enzyme \(\textbf{M}\) is zero (no jelly broken down). This is because enzyme \(\textbf{M}\) is adapted to alkaline conditions (optimum pH 10). The highly acidic environment at pH 2 causes the enzyme to become denatured. The shape of its active site changes so that it is no longer complementary to the substrate (the protein in the jelly), preventing the formation of enzyme-substrate complexes.
(c)
Name of enzyme L: Pepsin
Location: Stomach
(Explanation: Pepsin is a protease that functions in the acidic environment of the stomach, matching the optimum pH of 2 shown for enzyme L.)