Answer:
Inadequate calcium in the neuromuscular junction would directly affect THE RELEASE OF ACETYLCHOLINE FROM THE SYNAPTIC VESICLES.
Step-by-step explanation:
A neuromuscular junction refers to the chemical synapse that is formed as a result of contact between a muscle fiber and a motor neuron.
Calcium ions play vital roles in muscle actions. Calcium triggers the release of acetlycholine from motor neuron. Calcium ions are responsible for the triggering of muscle contraction cycle by the release of acetylcholine, they do this by binding to troponin, thus exposing the active binding sites located on actin. Immediately the sites are exposed, the myosin head bind to the sites forming a cross bridge.
When calcium ion is present in inadequate quantity in the neuromuscular junction, the release of acetylcholine will be inhibited, therefore the muscle contraction cycle will not be activated.