Select from the Response List the Compound or Ion That

question 28

Multiple Choice

Select from the response list the compound or ion that best fits the description: conjugate acid of HPO₄^2-.

• A) H₃PO₄
• B) H₂PO₄^-
• C) HPO₄^2-
• D) PO₄^3-

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Definitions:

First Messenger

A signaling molecule that binds to a receptor on the cell surface, initiating a signal transduction process that leads to the formation of an intracellular second messenger.

Ion Channel

An ion channel is a protein structure embedded in cell membranes that allows ions to pass through the membrane selectively.

Ligand

A molecule that binds specifically to another molecule, usually a larger one, in a reversible manner.

Acetylcholine

A common neurotransmitter released by cholinergic neurons, including motor neurons.