Which Observation Suggested the Involvement of a Second Messenger in Epinephrine's

question 50

Multiple Choice

Which observation suggested the involvement of a second messenger in epinephrine's effect on liver cells?

• A) Enzymatic activity was proportional to the amount of calcium added to a cell-free extract.
• B) Receptor studies indicated that epinephrine was a ligand.
• C) Glycogen breakdown was observed only when epinephrine was administered to intact cells.
• D) Glycogen breakdown was observed when epinephrine and glycogen phosphorylase were combined.
• E) Epinephrine was known to have different effects on different types of cells.

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Definitions:

Sensory Memory

A type of storage that holds sensory information for a few seconds or less.

Long-term Memory

A kind of memory that holds information for a long duration, from several days to many years.

Memory

The cognitive process of encoding, storing, and retrieving information, playing a vital role in learning and consciousness.

Retain Information

The ability or process of keeping or holding knowledge in the memory for later recall or use.