Which of the Following Statements Is True

question 99

Multiple Choice

Which of the following statements is true?

• A) Glycogen phosphorylase in liver cells is always active.
• B) cAMP is referred to as a "first messenger."
• C) Epinephrine directly activates adenylyl cyclase.
• D) cAMP is referred to as a "second messenger."
• E) Adenylyl cyclase is a protein kinase.

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Definitions:

Stems

The main structural axes of plants, responsible for supporting leaves, flowers, and fruits and for transporting fluids between them.

F.C. Steward

A botanist known for his pioneering work in plant physiology and tissue culture techniques.

Plant Physiologist

A scientist who studies the physical and chemical functions of plants, including how plants respond to their environment.

Callus Cell

A type of undifferentiated cell that forms during the healing of wounds in plants, also used in tissue culture for plant propagation.