Question

question 19
enzymes speed up chemical reactions by.
a breaking the bonds between molecules.
b lowering the activation energy of the reaction.
c assembling chemical bonds.
d increasing the cells metabolism.
e increasing the activation energy of the reaction.

question 20
another term for vitamins and minerals is “micronutrients” because they are.
a very small compared to other molecules in the body.
b only needed in small amounts by our body.
c used by very few reactions in the body.
d not very nutritionally dense.
e used by smaller cells more than by larger cells.

Explanation:

• For Question 19: Enzymes are biological catalysts. They work by reducing the activation - energy barrier required for a chemical reaction to occur, thus speeding up the reaction.
• For Question 20: Micronutrients like vitamins and minerals are called so because the body needs them in small quantities for various physiological functions.

Answer:

Question 19: B. lowering the activation energy of the reaction.
Question 20: B. only needed in small amounts by our body.