<prompt> Which of the following contains site of attachment of calcium ions that initiates muscle contraction?Troponin ITroponin TTroponin CMyosin  <response>: Troponin T binds the troponin components to tropomyosin; troponin I inhibits the interaction of myosin with actin; and troponin C contains the binding sites for the Ca2 that helps to initiate contraction.Ganong 23 rd ed, pg 96 