Refer to the Figure

question 15

Essay

Refer to the figure.
Describe an experiment to test the hypothesis that PK2 is a key clock messenger responsible for regulating circadian behaviors. Base your experiment on the results shown below, which show activity levels for rats in two treatment groups. Explain your predictions if the hypothesis is supported, and if the hypothesis is not supported. Note that rats are usually active during the nighttime, and PK2 production is normally high during the daytime and low during the nighttime.

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Definitions:

Sarcoplasmic Reticulum

A specialized type of smooth endoplasmic reticulum found in muscle cells, responsible for storing and releasing calcium ions during muscle contraction and relaxation.

Smooth Muscle

A type of muscle tissue which is not under conscious control, found in the walls of internal organs such as the stomach, intestines, and blood vessels.

Goose Bumps

The phenomenon where the skin appears to have goosebumps due to the erection of hairs, typically caused by cold or emotional factors.

Left Ventricle

The Left Ventricle is one of the four chambers of the heart, responsible for pumping oxygenated blood through the aorta to the rest of the body.