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How acetylcholine works at the neuromuscular junction?

Acetylcholine is a small molecule that acts as a chemical messenger to propagate nerve impulses across the neuromuscular junction between a nerve and a muscle. When the nerve impulse from a motor neuron arrives at the tip of its axon, acetylcholine molecules stored there in vesicles are released into the synaptic gap.

What happens at the neuromuscular junction during muscle contraction?

Neuromuscular junction, also called myoneural junction, site of chemical communication between a nerve fibre and a muscle cell. The neuromuscular junction is analogous to the synapse between two neurons. This initiates the end-plate potential, the electrical event that leads to contraction of the muscle fibre.

What are the steps of neuromuscular junction?

Terms in this set (9)

  • Nerve impulse arrives at axon terminal of motor neuron and triggers release of acetylcholine (ACh)
  • ACh diffuses, binds to its receptors, and triggers muscle action potential.
  • Acetylcholinesterase destroys A C h so more action potentials don’t arise.

What is the second step of muscle contraction?

Second Step. Ach binds to Ach Receptor on muscle cell. Fifth Step. Calcium is released from the sarcoplasmic reticulum. Ninth Step.

What is the first step of the sliding filament theory?

The Sliding Filament Theory For a contraction to occur there must first be a stimulation of the muscle in the form of an impulse (action potential) from a motor neuron (nerve that connects to muscle). Note that one motor neuron does not stimulate the entire muscle but only a number of muscle fibres within a muscle.

What is the correct order of events in the sliding filament theory of muscle contraction?

The correct order is: 6) Sarcoplasmic reticulum releases calcium ions, 2) Calcium ions bind to troponin, 5) Tropomyosin moves to expose active sites of actin, 4) ATP is split into ADP and P, 1) Myosin head binds to actin, 7) ADP and P released from myosin, 3) Myosin cross-bridges bend, pulling actin toward center of …

What is the correct order of the excitation contraction of skeletal muscle?

The sequence of events in twitch skeletal muscle involves: (1) initiation and propagation of an action potential along the plasma membrane, (2) spread of the potential throughout the transverse tubule system (T-tubule system), (3) dihydropyridine receptors (DHPR)-mediated detection of changes in membrane potential, (4) …

What is the sliding filament model of muscle contraction?

The sliding filament model describes the process used by muscles to contract. It is a cycle of repetitive events that causes actin and myosin myofilaments to slide over each other, contracting the sarcomere and generating tension in the muscle.

Can muscles regenerate when damaged?

When the muscle is damaged, these cells are stimulated to divide. After dividing, the cells fuse with existing muscle fibres, to regenerate and repair the damaged fibres. The skeletal muscle fibres themselves, cannot divide. However, muscle fibres can lay down new protein and enlarge (hypertrophy).