physioex9.0 exercise 3 activity 8

Activity 8,
      Question 1: When the stimulus intensity is increased, what changes: the number of synaptic vesicles released or the amount of neurotransmitter per vesicle?
      Question 2: What happened to the amount of neurotransmitter release when you switched from the control extracellular fluid to the extracellular fluid with no Ca2+?
      Question 3: What happened to the amount of neurotransmitter release when you switched from the extracellular fluid with no Ca2+ to the extracellular fluid with low Ca2+?
      Question 4: How did neurotransmitter release in the Mg2+ extracellular fluid compare to that in the control extracellular fluid?
      Question 5: How does Mg2+ block the effect of extracellular calcium on neurotransmitter release?