C1.1 Enzymes and Metabolism [IB Biology SL/HL]

What is the primary function of enzymes in biological reactions?

• To increase the temperature of the reaction
• To speed up the rate of chemical reactions
• To change the products of the reaction
• To act as substrates in the reaction

Which of the following best describes metabolism?

• The process of breaking down food into energy
• The conversion of light energy into chemical energy
• The process of cellular respiration only
• The sum of all enzyme-catalyzed reactions in cells

Which of the following statements accurately describes catabolic reactions?

• They require energy input to occur.
• They build larger molecules from smaller ones.
• They do not involve enzymes.
• They break down larger molecules into smaller components.

What is the significance of the active site of an enzyme?

• It is where the enzyme is produced
• It is where the substrate binds and the reaction occurs
• It determines the temperature at which the enzyme works best
• It is the part of the enzyme that gets consumed in the reaction

Which model describes how enzymes and substrates interact, allowing for shape changes?

• Active Site Model
• Enzyme-Substrate Complex Model
• Induced Fit Model
• Lock and Key Model

Which of the following statements about enzymes is true?

• Enzymes are consumed in the reactions they catalyze
• Enzymes can only catalyze one specific reaction
• Enzymes can be reused multiple times
• Enzymes work best at any temperature

What happens to an enzyme when it is denatured?

• It becomes a substrate
• It loses its specific shape and can no longer function
• It becomes more effective at catalyzing reactions
• It retains its original shape and function

How does temperature affect enzyme activity?

• Enzyme activity decreases at all temperatures.
• There is an optimal temperature for enzyme activity.
• Temperature has no effect on enzyme activity.
• Higher temperatures always increase enzyme activity.

How does increasing substrate concentration affect enzyme activity?

• It always decreases the reaction rate
• It has no effect on the reaction rate
• It increases the reaction rate until a maximum is reached
• It causes the enzyme to denature

What is activation energy in the context of enzyme-catalyzed reactions?

• The energy released during a reaction
• The energy required to initiate a chemical reaction
• The energy needed to break down substrates
• The energy that enzymes consume