Steps of Muscle Contraction Practice Problems

According to the sliding filament theory, the sarcomere's I band (isotropic bands) shortens during muscle contraction. The I band is the area of the sarcomere where the Z discs are anchored. As the sarcomere shortens during muscle contraction, the I band becomes narrower. What happens to the Z-discs during this process?

Which of the following is NOT a true statement regarding the action of acetylcholine (ACh) in muscle contraction?

Which of the following examples best illustrates the summative effect of multiple motor unit activations?

Which of the following structures is not a part of the neuromuscular junction?

During action potential, the excitation-induced release of calcium ions from the sarcoplasmic reticulum is triggered by :

What is the role of calcium ions in the neuromuscular junction?

Axon terminals play an essential role by releasing the neurotransmitters of the presynaptic cells. What chemical is contained in vesicles within the axon terminals?

Which of the following is responsible for the termination of neuronal transmission?

Which of the following statements is true regarding myoglobin?

Which of the following proteins is found in muscle tissue and has a higher affinity for oxygen?

What is the function of the fixator muscles?

What is the small fluid-filled gap between the neuron and muscle fiber membranes called?

Which of the following statements best describes fused tetanus?

Which of the following processes occur when muscles work at a high intensity and cannot receive enough oxygen for aerobic respiration?

All the myosin molecules within the thick filament are arranged with their tails pointing towards the

Identify the correct order of the muscle contraction cycle.

Which of the following triggers the release of acetylcholine into the synaptic cleft?

Which of the following happens during the resting state of the muscle contraction cycle?

What is the role of calcium in muscle contraction:

What is the main form of stored energy found in muscle cells:

Relaxation of muscle fibers is regulated by which element:

Which of the following will ensure that a marathon runner has enough energy to finish the race?

What is the term used to describe the singular contraction in the muscle fibers of a motor unit induced by a single action potential originating from a motor neuron?

Which kind of muscle contraction involves the shortening of muscles while producing force to overcome resistance?

Which of the following is a non-striated muscular tissue that contracts and relaxes automatically, without conscious control?

A patient is admitted to the hospital with symptoms suggestive of a heart attack. The healthcare provider orders blood tests to determine if a heart attack has occurred. Which of the following tests would aid in determining if a patient with suggestive symptoms of a heart attack has indeed experienced one?

Which of the following channels opens when a nerve impulse reaches the axon terminal at the neuromuscular junction?

What occurs when there is an influx of sodium ions into the muscle fiber greater than the efflux of potassium ions from the muscle fiber after the ACh binds and opens the ion channels?

Baclofen can act as a GABA-B receptor agonist. Therefore, Baclofen can serve as a:

Which ions are released from the sarcoplasmic reticulum triggered by the action potentials propagated by the T tubules?

Which of the following is considered the immediate energy source for muscle contraction and is rapidly depleted during intense exercise?

Which of the following muscles is predominantly composed of slow-twitch fibers?

Which of the following does not occur during the initial phase of myogram tracing?

Which type of muscle contraction occurs when the muscle length remains constant throughout the contraction phase?

Rigor mortis is a phenomenon that occurs after death where the muscles of the body undergo stiffening and contraction. Which of the following is the main reason why a dead body may experience a Rrgor mortis?

Identify the incorrectly matched pair.

Why does a person breathe heavily after exercise?

Which of the following is the fastest pathway for regenerating ATP during muscle activity?

What is the metabolic product in the anaerobic pathway that causes pain in the muscles?

Which of the following is responsible for the ability of smooth muscle to maintain contraction over long periods of time?