Question

1. describe how an enzyme speeds up a chemical reaction within a cell.

Explanation:

Enzymes are biological catalysts. They lower the activation energy (the minimum energy required for a reaction to occur) of a chemical reaction. Enzymes have an active site where the substrate (the reactant molecule) binds. This binding forms an enzyme - substrate complex. The enzyme can stress chemical bonds in the substrate, orient substrates correctly for the reaction, or provide a microenvironment that is favorable for the reaction. By lowering the activation energy, more substrate molecules have enough energy to undergo the reaction, thus speeding up the chemical reaction.

Answer:

Enzymes speed up chemical reactions within a cell by lowering the activation energy of the reaction. They have an active site that binds to the substrate, forming an enzyme - substrate complex. Through mechanisms like stressing bonds, proper substrate orientation, or creating a favorable microenvironment, the activation energy is reduced, allowing more substrate molecules to react and increasing the reaction rate.