If HCO₃^- that Is Radioactively Labeled with ¹³C Is Available

question 53

Multiple Choice

If HCO₃^- that is radioactively labeled with ¹³C is available, which carbon atom in the molecule below would ultimately be expected to be radioactive?

• A) A
• B) B
• C) C
• D) D

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Definitions:

Cyclic Adenosine

A cyclic form of adenosine monophosphate important in intracellular signaling processes.

Serotonin

A neurotransmitter of the biogenic amine group; important in mood and helps regulate the sleep–wake cycle.

Dopamine

A neurotransmitter of the biogenic amine group; important in motor function.

cAMP Signal Transduction

A cellular signaling pathway involving the secondary messenger cyclic AMP (cAMP) which mediates a variety of physiological responses.