Answer:
24. A chemical reaction is a process in which some substances change into different substances
25. A substance capable of initiating or speeding up a chemical reaction
26. protein macromolecules
27. by lowering the activation energy needed for the reaction to start.
28. Enzymes allow reactions to occur at the rate necessary for life. In animals, an important function of enzymes is to help digest food.
Step-by-step explanation:
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