Exhibit 21-4 ​

question 138

Multiple Choice

Exhibit 21-4
​

-Refer to Exhibit 21-4. Curve D is a(n) __________ cost curve.

• A)marginal
• B)average variable
• C)average total
• D)average fixed

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Definitions:

Action Potentials

short-lasting events in which the electrical membrane potential of a cell rapidly rises and falls, allowing neurons to transmit signals.

Synaptic Gaps

The small spaces between neurons across which neurotransmitters travel to transmit signals from one neuron to another.

Neurotransmitters

Chemicals released by one neuron (usually the presynaptic neuron), which trigger a response in another neuron (usually the postsynaptic neuron); the chief means of communication among neurons.

Presynaptic Neuron

A neuron that sends a signal toward a synaptic cleft, releasing neurotransmitters to stimulate or inhibit the postsynaptic cell.