NAS 2 Challenge Exam (2023/2024) | Grade A| More than 100 Questions and Verified Answers

NAS 2 Challenge Exam (2023/2024) | Grade A| More than 100 Questions and Verified Answers QUESTION Describe The Krebs cycle, its location in the prokaryotic and eukaryotic cell, name the three organic molecules it can use to make ATP, and name the waste product it produces Answer: - Eukaryotic cells.: The matrix of the mitochondria - Prokaryotic cells: Cytoplasm - Pyruvate, Fatty acids, and Amino acids - CO2 and H2O QUESTION Describe the electron transport chain, its location in the prokaryotic and eukaryotic cell and number of ATP molecules it produces Answer: - Aerobic (needs O2) 1. Hydrogen atoms are delivered in the form of NADH+H+ and FADH2 to carrier proteins on the cristae of the mitochondria 2. The atoms are split into H+ (protons) and electrons 3. The electrons are shuttled along the inner mitochondrial membrane, releasing energy 4. The energy released by the electrons is used to pump H+ (protons) into the intermembrane space through carrier proteins - Eukaryotic cells: Cristae of the mitochondria - Prokaryotic cells: Plasma membrane - 28 ATP QUESTION Explain how H+ are sequestered in the mitochondrial intermembrane space Answer: This pumping of H+ into the intermembrane space creates an electrochemical proton (H+) gradient across the mitochondrial inner membrane, establishing potential energy across the membrane QUESTION Explain how H+ are used to make ATP, include the role of ATP Synthase Answer: 1. H+ diffuses back to the mitochondrial matrix along its concentration gradient via ATP Synthase port 2. ATP Synthase uses the energy released from the H+ to attach a phosphate group to ADP to form ATP QUESTION Explain the role of oxygen in the electron transport phase of aerobic respiration, and how it is used to make metabolic water Answer: (The separated electrons are delivered to oxygen, forming water.) 1. Oxygen binding with free H+ in the mitochondrial matrix producing water helps to: Reduce the concentration of H+ in the mitochondrial matrix 2. Establish a concentration gradient 3. Maintain a slightly negative charge on the inside of the inner membrane (electrochemical gradient) QUESTION State the total number of ATP molecules produced by cellular respiration from one glucose molecule