Questions: Question 3 1 pts An enzyme acts to Raise the activation energy needed to start the reaction Lower the activation energy needed to start the reaction Convert the activation energy into kinetic energy Stop a chemical reaction

The answer is the second one: Lower the activation energy needed to start the reaction.

Explanation for each option:

1. Raise the activation energy needed to start the reaction: This is incorrect. Enzymes do not raise the activation energy; they function to make reactions occur more easily by lowering the activation energy.

2. Lower the activation energy needed to start the reaction: This is correct. Enzymes are biological catalysts that speed up chemical reactions by lowering the activation energy required for the reaction to proceed.

3. Convert the activation energy into kinetic energy: This is incorrect. Enzymes do not convert activation energy into kinetic energy. They simply lower the activation energy barrier, allowing the reaction to proceed more readily.

4. Stop a chemical reaction: This is incorrect. Enzymes do not stop chemical reactions; they facilitate them by lowering the activation energy.

Summary: Enzymes act to lower the activation energy needed to start a reaction, thereby increasing the rate at which the reaction occurs.