AP Biology Exam Review Practice Questions and Answers

AP Biology Exam Review Practice Questions and Answers DNA/Biochemestry Test -- 1. The digestive enzyme pepsin works in the acidic environment of the stomach to hydrolyze peptide bonds. On which macromolecules does pepsin act? A. carbohydrate B. protein C. DNA D. lipid B. Protein 2. Egg whites consist primarily of water and the protein albumin. When you fry an egg, why does the egg white turn from clear to white? A. The protein becomes dissociated. B. The protein acquires tertiary structure. C. The protein becomes denatured. D. The protein becomes dehydrated C. The Protein becomes denatured 3. Margarine is made by hydrogenating vegetable oils so that they take on the consistency of butter. Which of the following is the chemical basis for this change from a liquid to a solid? A. Fats are changed from unsaturated to saturated, allowing them to solidify. B. Fats are changed from saturated to unsaturated, allowing them to solidify. C. Trans-fatty acids are changed from unsaturated to saturated, allowing them to solidify. D. Trans fatty acids are changed from saturated to unsaturated, allowing them to solidify. A. Fats are changed from unsaturated to saturated, allowing them to solidify. 4. People who are lactose intolerant can often consume some products made from milk such as cheese and yogurt. By comparison, people with a true milk allergy, which involves an immune response to milk protein, cannot consume milk or products made from milk. Given this information, which of the following statements is true? A. The protein that causes a true milk allergy is lactose. B. All people who are lactose intolerant are also allergic to milk. C. Yogurt contains live and active cultures of Lactobacillus acidophilus bacteria and therefore prevents an allergic response in people with a true milk allergy. D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies. D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies. 5. Shivering is the result of uncontrollable contractions of skeletal muscle tissue in an effort to increase heat production and raise body temperature. How does this process relate to ATP hydrolysis? A. ATP is converted directly to heat. B. Muscle contractions in the form of shivering produces heat and warms the body. C. ATP hydrolysis causes muscle contraction. D. Muscle contractions require ATP hydrolysis. Energy is liberated by ATP hydrolysis and converted into heat. D. Muscle contractions require ATP hydrolysis. Energy is liberated by ATP hydrolysis and converted into heat.