5. Enzymes

Question 1

What is Activation Energy?

Answer 1

• Chemical reactions involve the collision of two reactants.
• A successful collision results in the formation of products.
• A successful collision occurs when the reactants collide with a minimum amount of energy called activation energy.
• The amount of activation energy determines the rate of a reaction.
• Reactions with a high activation energy proceed slowly as fewer molecules posses the energy.
• Reactions with low activation energy proceed more rapidly as more molecules posses the energy.

Question 2

What are Enzymes?

Answer 2

• Are Biological catalysts that increase the rate of reactions in cells by lowering the activation energy.
• Enzymes catalyse reactions by binding with a substrate forming an enzyme-substrate complex
• Substrates bind to a specific region of the enzyme called the active site.
• The shape of the active site is complementary to the substrate.
• The unique 3D shape of the enzyme and its active site ensures that the enzyme binds to a specific substrate.