On p. 84 of the text, in the Thinking Clearly section, the conduction action potentials and activation of neurotransmitters is related to a row of mousetraps on a wobbly shelf. Think of another analogy you can use to describe the conduction of action potentials and activation of neurotransmitters.

Answer 1

What you need is an analogy that has something building up until a critical level is reached, and then an action will result.

Your searching for your own analogy will help you understanding of the concepts.