AP BIOLOGY

Detailed explanation-1: -Temperature: Raising temperature generally speeds up a reaction, and lowering temperature slows down a reaction. However, extreme high temperatures can cause an enzyme to lose its shape (denature) and stop working. pH: Each enzyme has an optimum pH range. Changing the pH outside of this range will slow enzyme activity.

Detailed explanation-2: -The altering of a protein’s molecular structure is known as denaturation. During denaturation, many of the weak connections and interactions (such as hydrogen bonds) inside a protein molecule that is responsible for the highly ordered structure of the protein in its natural (native) state, are broken.

Detailed explanation-3: -Changes in pH can cause an enzyme to denature (lose their precise shape) and the substrate won’t fit into the active site. Once an enzyme has denatured, it will not function again. The pH at which enzyme activity is highest is known as the optimum pH. Every enzyme will have its own optimum pH.

Detailed explanation-4: -Denaturing due to extreme temperatures is permanent and means that the rate of reaction will decrease or may stop completely. Always use the term ‘denature’ to describe an enzyme that has changed shape to the point where it can no longer bind to the SUBSTRATE and CATALYSE the reaction.

Detailed explanation-5: -When an enzyme denatures, its active site changes its shape, as you can see in this diagram. This is because the protein structure of the enzyme has changed. You might notice that the active site is no longer a complementary shape to a specific substrate molecule.