This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'The heme prosthetic group is found in \nSelect and explain. \nA. Myoglobin, B. Cytochrome oxidase, C. Xanthine oxidase, D. Tyrosine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Myoglobin is a monomeric protein that acts as a secondary oxygen transporter and binder in the muscle tissues. \nFurthermore, the tertiary feature of myoglobin resembles water-soluble\xa0globule protein characteristics. \nThe diffusion and use of oxygen in the muscles are necessary for the bodily system processes such as respiration.\nMyoglobin has 8\xa0right-handed\xa0a-helices separately forming a polypeptide chain and each contains a single heme\xa0prosthetic\xa0group with a central bound iron atom.', 'role': 'assistant'}]