Explanation:
because the pressure exerted by artery is more than that of vein due to its narrow lumen and thick walls...causing it difficult to clot.
Answer:
E. bind to troponin which moves the tropomyosin
Explanation:
calcium ions bind to troponin, causing conformational changes in troponin that allow tropomyosin to move away from the myosin binding sites on actin. Once the tropomyosin is removed, a cross-bridge can form between actin and myosin, triggering contraction