Muscles Unit Section 5.3 and 5.4

The gap between the nerve cell and sarcolemma is the ____ ___.

• Synaptic cleft

• Neurotransmitter

• Motor unit

• Neuromuscular junction

What is the specific neurotransmitter that stimulates the movement of skeletal muscles?

• GABA

• Acetylcholine

• Serotonin

• Dopamine

Once the action potential reaches the end of the pre-synaptic terminal what takes place?

• ACh is released into the synaptic cleft.

• Calcium is pumped into the sarcolemma.

• Calcium is pumped into the presynaptic terminal.

• The muscle contracts.

Once calcium is pumped into the presynaptic terminal what happens?

• The muscle contracts

• ACh is released into the synaptic cleft.

• Sodium pumps into the sarcolemma.

• The muscle contracts.

What is the name of the component that houses the neurotransmitters?

• Synaptic cleft

• Acetylcholine

• Receptors

• Synaptic vesicles

Region where a motor neuron comes in close contact with a muscle cell.

• neurotransmitter
• muscular dystrophy
• muscle tension
• neuromuscular junction

What causes the sodium channels on the muscle to open?

• Acetylcholine binds to the Na+ channel

• Acetylcholine binds to the synaptic vesicles

• the Ca2+ channels open

• The action potential is generated in the muscle cell

What is the role of acetylcholinesterase? (two answers)

• It allows acetylcholine to leave the synaptic cleft

• It creates acetylcholine out of acetic acid and choline

• It breaks acetylcholine down into choline and acetic acid

• It helps acetylcholine re-enter the neuron

What happens at the neuromuscular junction?

• A sensory neuron communicates with a motor neuron

• An action potential jumps from the muscle to the neuron

• A nerve signal traveling down a motor neuron can jump over to the muscle cell

• Muscle cells contract in response to a sensory neuron

Once ACh binds to receptor cells on the sarcolemma, what takes place?

• Sarcolemma becomes temporarily permeable to sodium.

• The muscle contracts.

• Calcium is pumped into the axon terminal.

• Synaptic vesicles move to the end of the terminal.