The major transmitter released by the adrenal medulla is ____________________

An ion channel that opens in response to a physical, mechanical stimulus is known as a:

a. Pressure-gated (modality-gated) channel b. Voltage-gated channel c. Ligand-gated channel

The greater the ________, the less magnification and distortion present on an image.

Fill in the blank(s) with the appropriate word(s).