Inadequate calcium in the neuromuscular junction would directly affect process

Release of acetylcholine from the synaptic vesicles

Explanation: Acetylcholine is a neurotransmitter of nerve impulses within the central and peripheral nervous systems. It is formed during the esterfication reaction between acetic acid and choline. After its formation, acetylcholine is transprted to a vesicle, where a transporter protein actively pumps the choline into the vesicle. Acetylcholine is stored until a need arises for it to be released.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.