Figure 10.6

Structure of the

Neuromuscular Junction

Process Diagrams Step-by-Step

Copyright © 2007 by John Wiley & Sons, Inc.

1

Axon terminal

Axon terminal

Axon collateral ofsomatic motor neuron

Sarcolemma

Myofibril

ACh is releasedfrom synaptic vesicle

Junctional fold

Synaptic vesiclecontainingacetylcholine(ACh)

Sarcolemma

Synaptic cleft(space)

Motor end plate

Synaptic cleft(space)

(a) Neuromuscular junction

(b) Enlarged view of the neuromuscular junction

(c) Binding of acetylcholine to ACh receptors in the motor end plate

Synapticend bulb

Synapticend bulb

Neuromuscularjunction (NMJ)

Synaptic end bulb

Motor end plate

Nerve impulse

1

1

Axon terminal

Axon terminal

Axon collateral ofsomatic motor neuron

Sarcolemma

Myofibril

ACh is releasedfrom synaptic vesicle

ACh binds to Achreceptor

Junctional fold

Synaptic vesiclecontainingacetylcholine(ACh)

Sarcolemma

Synaptic cleft(space)

Motor end plate

Synaptic cleft(space)

(a) Neuromuscular junction

(b) Enlarged view of the neuromuscular junction

(c) Binding of acetylcholine to ACh receptors in the motor end plate

Synapticend bulb

Synapticend bulb

Neuromuscularjunction (NMJ)

Synaptic end bulb

Motor end plate

Nerve impulse

Na+

1

22

1

Axon terminal

Axon terminal

Axon collateral ofsomatic motor neuron

Sarcolemma

Myofibril

ACh is releasedfrom synaptic vesicle

ACh binds to Achreceptor

Junctional fold

Synaptic vesiclecontainingacetylcholine(ACh)

Sarcolemma

Synaptic cleft(space)

Motor end plate

Synaptic cleft(space)

(a) Neuromuscular junction

(b) Enlarged view of the neuromuscular junction

(c) Binding of acetylcholine to ACh receptors in the motor end plate

Synapticend bulb

Synapticend bulb

Neuromuscularjunction (NMJ)

Synaptic end bulb

Motor end plate

Nerve impulse

Muscle action potential is produced

Na+

1

2

3

2

1

Axon terminal

Axon terminal

Axon collateral ofsomatic motor neuron

Sarcolemma

Myofibril

ACh is releasedfrom synaptic vesicle

ACh binds to Achreceptor

Junctional fold

Synaptic vesiclecontainingacetylcholine(ACh)

Sarcolemma

Synaptic cleft(space)

Motor end plate

Synaptic cleft(space)

(a) Neuromuscular junction

(b) Enlarged view of the neuromuscular junction

(c) Binding of acetylcholine to ACh receptors in the motor end plate

Synapticend bulb

Synapticend bulb

Neuromuscularjunction (NMJ)

Synaptic end bulb

Motor end plate

Nerve impulse

Muscle action potential is produced

ACh is broken down

Na+

1

2

4

3

2