Neuromuscular Junction Review

Front

What is the neuromuscular junction (NMJ)?

Back

The NMJ is a specialized synapse where a motor neuron communicates with a muscle fiber, facilitating muscle contraction.

Front

What neurotransmitter is released at the NMJ?

Back

Acetylcholine (ACh) is the neurotransmitter released at the NMJ, which binds to receptors on the muscle fiber.

Front

What is the role of the synaptic cleft in the NMJ?

Back

The synaptic cleft is the small gap between the axon terminal of the motor neuron and the motor end plate of the muscle fiber, where neurotransmitters are released.

Front

What is the motor end plate?

Back

The motor end plate is the specialized region of the muscle fiber's sarcolemma that contains receptors for acetylcholine.

Front

How does a motor neuron initiate muscle contraction?

Back

A motor neuron sends an action potential that triggers the release of acetylcholine at the NMJ, leading to muscle contraction.

Front

What happens to acetylcholine after it binds to its receptors?

Back

After binding, acetylcholine causes depolarization of the muscle fiber membrane, leading to muscle contraction.

Front

What is the function of the axon terminal in the NMJ?

Back

The axon terminal is the end of the motor neuron that releases acetylcholine into the synaptic cleft.

Front

What is the relationship between a synapse and the NMJ?

Back

The NMJ is a specific type of synapse that connects a motor neuron to a muscle fiber.

Front

What occurs in the synaptic cleft during muscle contraction?

Back

Acetylcholine is released into the synaptic cleft, binds to receptors on the muscle fiber, and initiates a contraction.

Front

What is the significance of the sarcolemma in muscle contraction?

Back

The sarcolemma is the cell membrane of the muscle fiber that contains receptors for acetylcholine and is essential for muscle contraction.