Neuromuscular Junction

Front

What is a motor unit?

Back

A motor unit consists of one neuron and all the skeletal muscle cells it stimulates.

Front

What is the synaptic cleft?

Back

The synaptic cleft is the gap between the nerve cell and the sarcolemma.

Front

What happens when the action potential reaches the end of the axon terminal?

Back

ACh (acetylcholine) is released into the synaptic cleft.

Front

What are synaptic vesicles?

Back

Synaptic vesicles are components that house neurotransmitters.

Front

What occurs when ACh binds to receptor cells on the sarcolemma?

Back

The sarcolemma becomes temporarily permeable to sodium.

Front

Define neuromuscular junction.

Back

The neuromuscular junction is the synapse or junction between a motor neuron and a skeletal muscle fiber.

Front

What role does acetylcholine (ACh) play in muscle contraction?

Back

ACh is a neurotransmitter that transmits signals from the neuron to the muscle, initiating contraction.

Front

What is the function of acetylcholinesterase?

Back

Acetylcholinesterase is an enzyme that breaks down ACh in the synaptic cleft, stopping the signal transmission.

Front

Explain the process of muscle contraction at the neuromuscular junction.

Back

When ACh is released, it binds to receptors on the sarcolemma, leading to depolarization and muscle contraction.

Front

What is the role of calcium ions in muscle contraction?

Back

Calcium ions are released from the sarcoplasmic reticulum and bind to troponin, allowing muscle contraction to occur.