as the question is incomplete i have attached the full question with solution. see attachment. This question is matching pair therefore i compiled it in a picture format for better understanding.
Explanation:
Before a chemical reaction, the elements and compounds which are about to take part in the reaction are known as reactants.
And, when the chemical reaction takes place between the given elements and compounds then they change into products.
For example, we take sodium and chlorine elements and before any chemical reaction they are the reactants.
But when a chemical reaction takes place between sodium and chlorine then it results into the formation of sodium chloride which is the product.
Cells don't grow very big because they have to be able to diffuse through material easily. Also, when cells are small and plentiful they are easy to replace when damaged.
