This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Biochemistry
[{'content': 'Source of energy for a running race athlete for the initial 3 minutes of running \nSelect and explain. \nA. Free fatty acid, B. Creatine phosphate, C. Muscle glycogen, D. Blood Glucose', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Systems for energy during strenuous exercise or running 1. First System-Phosphagen system (8-10 seconds) - Immediate source of energy for Muscles is Creatine Phosphate. - But this is of limited supply in muscles, so depleted quickly 2. Second system -Anaerobic Glycolysis or Lactate system. (for 1-3 minutes ) - This system derives ATPs using Glucose derived from Muscle Glycogen 3.Third system -Aerobic System (or Mitochondrial Respiration) - can use carbohydrates, Fats, or Proteins to produce energy. - Slowest in providing energy, but more efficient than the other two systems - This system uses mainly TCA & ETC. Reasons for use of Phosphocreatine:- - Does not uses O2 - Does not produce lactate - Quickest source of energy - Most direct form of energy production', 'role': 'assistant'}]