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: Physiology
[{'content': 'Function of Phospholamban is : \nSelect and explain. \nA. Regulates Na K Pump, B. Transpos calcium out of the mitrochondria, C. Binds actin with myosin, D. Collects calcium into the sarcoplasmic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Collects calcium into the sarcoplasmic reticulum Phospholamban is a protein contained within the sarcoplasmic reticulum that inhibits the activity of sarcoplasmic calcium pumpQ. Inactivation of phospholamban results in an increase in calcium sequestration by sarcoplasmic reticulum.Q - In cardiac muscle, the rapid sequestration of Ca2+ shoens the duration of contraction. - In smooth muscle, sequestration causes the muscle to relax. - Phospholamban has little effect on skeletal muscle contraction.', 'role': 'assistant'}]