Enzyme Function and Activation Energy

The video tutorial explains the role of enzymes in chemical reactions, focusing on how they lower activation energy to catalyze reactions. It covers the basics of chemical reactions, the function of enzymes, and the induced fit model. The tutorial also discusses the role of enzymes in catabolic and anabolic reactions, as well as the energy changes in exothermic and endothermic reactions. The video concludes with a review and test preparation tips for AP Biology students.

What is the primary role of activation energy in chemical reactions?

• To decrease the speed of the reaction

• To increase the temperature of the reactants

• To initiate the reaction by overcoming an energy barrier

• To change the products of the reaction

How do enzymes affect the activation energy of a reaction?

• They increase the activation energy required

• They provide energy to the reactants

• They lower the activation energy needed

• They change the products of the reaction

Why are enzymes not considered reactants in a chemical reaction?

• They increase the activation energy

• They are consumed in the reaction

• They alter the products of the reaction

• They do not change the free energy of the products

Which model suggests that enzymes change shape to fit the substrate?

• Induced Fit Model

• Lock and Key Model

• Catalyst Model

• Substrate Model

In a catabolic reaction facilitated by enzymes, what typically happens?

• Energy is absorbed

• Bonds are formed

• Energy is released

• No energy change occurs

What is a common misconception about exothermic reactions?

• They do not require activation energy

• They do not involve enzymes

• They absorb energy from the environment

• They always occur spontaneously

How do enzymes facilitate anabolic reactions?

• By forcing substrates together

• By releasing energy

• By breaking down molecules

• By increasing the temperature

What is the role of enzymes in exothermic reactions?

• They increase the energy released

• They provide the initial spark to start the reaction

• They change the products of the reaction

• They absorb energy from the environment

What is the difference between activation energy and overall energy change in a reaction?

• Overall energy change is always greater than activation energy

• Activation energy is the initial energy needed to start a reaction

• Overall energy change includes activation energy

• Activation energy is the total energy change

What happens to enzymes after they facilitate a reaction?

• They reset and can be used again

• They are used up

• They are permanently altered

• They become part of the products