Muscle Physiology Lab Report

Whether you are sitting at a desk doing a physiology lab report, or playing a sport in the park, you are constantly using muscles to accomplish those tasks. The fingers that are used to type the lab report rely on individual myofibrils to contract and cause movement. However, this mechanism occurs on a microscopic level, and predominantly in the myofibers. When a motor neuron experiences an action potential it releases acetylcholine to the motor-end plate which binds to a receptor on the myofibril called the nicotinic acetylcholine receptor. This interaction causes the fiber to become more positive, stimulating depolarization. There are specific invaginations in the muscle fiber called the T-tubules which helps depolarize and activate other …show more content…
Thus, when the ryanodine receptors are activated it allows more calcium to leave the SR and into the cytoplasm. Calcium is exceedingly important in muscle function, because it binds to a component on the actin called the troponin. A muscle fiber is made up of countless sarcomeres that contains myosin and actin filaments.To have a contraction, myosin and actin must form a cross-bridge and induce a power stroke. To phenomenon occurs when two important molecules are present, calcium and ATP Myosin is a thick filament that attaches to a binding site on the actin, which is a thin filament.When the troponin-tropomyosin blocks that binding sites of the myosin, myosin heads cannot binds and form a cross-bridge. When the motor neuron experiences and action potential and releases acetylcholine, this neurotransmitter releases lots of calcium so that it could bind to a region on the troponin called the TnC. As calcium binds to the TnC, the troponin-tropomyosin complex disembody, and myosin binds to the myosin binding site. ATP is also very important because this is the molecule that actually creates the power stroke, or the movement of the