How does a motor neuron stimulate a skeletal muscle contraction? What is the sliding filament theory? Describe cross-bridge cycling. Where does the ATP needed for a muscle contraction come from? Explain why an action potential in a single motor neuron can cause multiple muscle fibers to contract.

Muscle contraction is described by the sliding filament model of contraction. ACh is the neurotransmitter that binds at the neuromuscular junction (NMJ) to trigger depolarization, and an action potential travels along the sarcolemma to trigger calcium release from SR.

2023年4月1日 · The complex process leading to muscle contraction, called excitation-contraction coupling, begins when an action potential causes depolarization in the myocyte membrane. The depolarization is spread via the transverse (T) tubules, invaginations of the muscle cell membrane, that help spread depolarization signals to the entire muscle fiber.

2023年5月1日 · Skeletal muscle contraction begins first at the neuromuscular junction, which is the synapse between a motoneuron and a muscle fiber. Propagation of action potentials to the motoneuron and subsequent depolarization results in the opening of voltage-gated calcium (Ca2+) channels of the presynaptic membrane.

Muscle contraction begins when the nervous system generates a signal. The signal, an impulse called an action potential, travels through a type of nerve cell called a motor neuron. The neuromuscular junction is the name of the place where the motor neuron reaches a muscle cell.

The action potential invades T-tubules and causes the L-type calcium channels to open, which in turn causes ryanodine receptors (RyRs) in the SR to open and release calcium, which stimulates contraction.

Excitation–contraction coupling (ECC) occurs when depolarization of skeletal muscles (usually through neural innervation) results in a muscle action potential. This action potential spreads across the muscle's surface and into the muscle fiber's network of T …

From muscle cell action potentials to contractions. Sarcomere contraction relies on a surge of intracellular calcium which is initiated by an action potential that propagates through the muscle fiber. Action potentials of skeletal muscle fibers are …

An action potential is a special type of electrical signal that can travel along a cell membrane as a wave. This allows a signal to be transmitted quickly over long distances. In skeletal muscle, cross-bridge formation and contraction requires the presence of calcium (Ca 2 +) inside the muscle cell. Excitation signaling of action potentials ...

Excitation–contraction coupling is the link (transduction) between the action potential generated in the sarcolemma and the start of a muscle contraction. The trigger for calcium release from the sarcoplasmic reticulum into the sarcoplasm is a neural signal.