What are enzymes? A. Proteins that speed up chemical reactions B. Carbohydrates that store energy C. Lipids that transport nutrients D. Nucleic acids that store genetic information

How do enzymes work? A. By increasing the amount of reactants in a reaction B. By decreasing the activation energy needed for a reaction to occur C. By binding to the product of a reaction D. By changing the pH of the environment

What is the lock and key model of enzyme function? A. Enzymes act as "keys" that unlock specific substrates B. Enzymes and substrates are both flexible and can bend to fit each other C. Enzymes and substrates are attracted to each other by electrostatic forces D. Enzymes and substrates both change shape during a reaction

What is an enzyme's active site? A. The location where a substrate binds to an enzyme B. The location of an enzyme's DNA sequence C. The location where an enzyme enters a cell D. The location where a reaction occurs

What factors can affect enzyme activity? A. pH, temperature, and concentration of substrate B. Time of day, weather, and altitude C. Clothing, hairstyle, and eye color D. Type of food eaten, music listened to, and favorite color

What happens when an enzyme is denatured? A. Its structure is permanently altered, so it can no longer function B. Its structure is temporarily altered, but it can still function C. Its active site becomes stronger, allowing it to bind to more substrates D. Its active site becomes weaker, preventing it from binding to substrates

What is an example of an enzyme-catalyzed reaction in the human body? A. The breakdown of glucose to produce ATP B. The binding of oxygen to hemoglobin C. The synthesis of DNA from nucleotides D. The contraction of muscle fibers

What is the difference between an enzyme and a catalyst? A. Catalysts are proteins, while enzymes are not B. Enzymes are specific to certain reactions, while catalysts are not C. Enzymes speed up reactions, while catalysts slow them down D. There is no difference - enzyme and catalyst are interchangeable terms

What is an inhibitor? A. A molecule that binds to an enzyme and prevents it from functioning B. A molecule that speeds up enzyme activity C. A molecule that activates an enzyme D. A molecule that has no effect on enzyme activity

What is allosteric regulation? A. The binding of a molecule to a site on an enzyme that is not the active site B. The binding of a substrate to an enzyme's active site C. The release of a reaction's products from an enzyme D. The conversion of an enzyme from its inactive to its active form