This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of protein and amino acid, Subject name: Biochemistry
Hemoprosthetic group is found in 
Select and explain. 
A. Myoglobin, B. Cytochrome oxidase, C. Xanthine oxidase, D. Tyrosine
A: Myoglobin
Answer: A: Myoglobin 
Explanation: Myoglobin is a monomeric protein that acts as a secondary oxygen transpoer and binder in the muscle tissues. Fuhermore, the teiary feature of a myoglobin resembles a water-soluble globule protein characteristics. The diffusion and use of oxygen in the muscles are necessary for the bodily system processes such as respiration. Myoglobin has 8 right-handed a-helices separately forming a polypeptide chain and each contains a single heme prosthetic group with a central bound iron atom.Ref: Text book of biochemistry for medical students. seventh edition, page no: 240 and 294