Which Molecule Acts as a Second Messenger in the Cascade

question 215

Multiple Choice

Which molecule acts as a second messenger in the cascade by which epinephrine stimulates the activation of the enzyme glycogen phosphorylase?

• A) Adenosine
• B) Caffeine
• C) Citric acid
• D) Cyclic AMP
• E) Adenylyl cyclase

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Definitions:

Cones

Cells in the eye's retina called photoreceptors are essential for perceiving colors and operate optimally in well-lit conditions.

Rods

Photoreceptor cells in the retina of the eye that are highly sensitive to light and enable vision in low-light conditions, but do not support color vision.

Cones

Photoreceptor cells in the retina of the eye that are responsible for color vision and function best in relatively bright light.

Color Opponent Processing

A theory in vision science suggesting that the human visual system interprets color by processing signals from cones and rods in an antagonistic manner.