Enzymes are ineffective after heating because they are
(1) proteins, and heat changes their physical shape, (2) carbohydrates and heat dissolves them, (3) too acidic, (4) bound to an acid, (5) none of these.
Question 2
Denaturation of proteins by heat occurs as protein molecules
(1) repel each other, (2) relax from their tertiary structure and form secondary bonds between molecules, (3) change to their tertiary structure and repel each other, (4) take up iron, (5) form fibrous strands and become more soluble.