Indicate whether each of the following statements regarding…
Indicate whether each of the following statements regarding skeletal muscle contraction is likely to be true or false. When a muscle cell receives a signal from the nervous system, voltage-gated calcium channels open in the T-tubule membrane. During muscle contraction, the Z discs move closer together as the myosin heads walk toward the plus ends of the actin filaments. When the cytoplasmic calcium concentration increases, a change in the conformation of troponin leads to changes in tropomyosin such that it blocks the binding of myosin heads to the actin filament. The changes in voltage across the plasma membrane that occur when a muscle cell receives a signal from the nervous system causes an influx of Ca2+ from the cytoplasm to the sarcoplasmic reticulum, which triggers a muscle contraction.