Neuromuscular Junction Quiz

What is the functional connection between a neuron and the cell it controls called?

• Axon terminal

• Synapse

• Sarcomere

• Neurotransmitter

What is the neurotransmitter responsible for skeletal muscle contraction?

• Dopamine

• Serotonin

• Glutamate

• Acetylcholine

Where is acetylcholine stored in the motor neuron?

• Sarcoplasmic reticulum

• Axon body

• Synaptic vesicles

• Sarcolemma

What happens when acetylcholine binds to receptors on the muscle fiber membrane?

• Membrane permeability to sodium and potassium ions increases.

• The sarcomere elongates.

• Calcium is absorbed by the motor neuron.

• The muscle fiber depolarizes completely.

What maintains the concentration gradients of sodium and potassium ions in a muscle cell?

• Synaptic vesicles

• Sodium/potassium pump

• Sarcoplasmic reticulum

• Acetylcholine

Tags

NGSS.HS-LS1-3

What is the role of the sodium/potassium pump?

• To block calcium release

• To generate action potentials

• To create a concentration gradient of sodium and potassium ions

• To synthesize acetylcholine

Tags

NGSS.HS-LS1-3

What happens when a motor neuron stimulates a muscle cell?

• Sodium ions enter the muscle cell faster than potassium ions leave.

• Potassium ions enter the muscle cell faster than sodium ions leave.

• Calcium is stored in the synaptic vesicles.

• The sarcomere lengthens.

What is triggered when sodium channels on the sarcolemma open?

• Calcium storage

• Synaptic vesicle fusion

• Action potential

• Sarcomere relaxation

Tags

NGSS.HS-PS2-5

Where does the action potential travel after spreading along the sarcolemma?

• Into the sarcoplasmic reticulum

• Into the synaptic cleft

• Into the mitochondria

• Into the transverse tubules

What does the action potential trigger in the sarcoplasmic reticulum?

• Sodium release

• Calcium release

• Potassium absorption

• Acetylcholine synthesis