Events of Excitation-Contraction Coupling [Part 1]

The video tutorial explains the process of skeletal muscle contraction, starting with the initial excitation by a motor neuron and ending with the contraction of the sarcomere. It covers the excitation-contraction coupling process, detailing the role of the motor neuron, action potential propagation, and the release of calcium from the sarcoplasmic reticulum. The tutorial also highlights the importance of the T tubule system in activating deeper muscle fibers.

What is the term used to describe the process that includes both excitation and contraction of muscles?

• Neural Activation

• Muscle Relaxation

• Excitation-Contraction Coupling

• Excitation-Relaxation Coupling

What neurotransmitter is stored in vesicles at the synaptic end bulb?

• Norepinephrine

• Dopamine

• Serotonin

• Acetylcholine

What triggers the release of acetylcholine from the synaptic end bulb?

• Calcium influx

• Potassium efflux

• Sodium influx

• Chloride influx

What type of ion channels open sequentially along the motor neuron axon to propagate the action potential?

• Ligand-gated chloride channels

• Voltage-gated calcium channels

• Voltage-gated sodium channels

• Ligand-gated potassium channels

What is the space between the axon and the motor endplate called?

• Neural synapse

• Neuromuscular junction

• Synaptic cleft

• Axonal gap

What happens when acetylcholine binds to its receptor on the motor endplate?

• Sodium influxes into the cell

• Potassium influxes into the cell

• Sodium effluxes from the cell

• Calcium effluxes from the cell

What is the role of the transverse tubule system in muscle contraction?

• To store calcium ions

• To propagate action potentials deeper into the muscle

• To release neurotransmitters

• To generate ATP

What is the function of the ryanodine receptor in muscle cells?

• To release calcium ions from the sarcoplasmic reticulum

• To release sodium ions

• To bind acetylcholine

• To store potassium ions

What is the primary role of the sarcoplasmic reticulum in muscle cells?

• To store calcium ions

• To store potassium ions

• To store sodium ions

• To store acetylcholine

What is the effect of calcium release from the sarcoplasmic reticulum on muscle contraction?

• It triggers muscle contraction

• It has no effect on muscle contraction

• It initiates muscle relaxation

• It inhibits muscle contraction