The Most Important Factor in Setting Our Internal 24-Hour Biological

question 45

Multiple Choice

The most important factor in setting our internal 24-hour biological clock is bright light,which signals the brain's _____ to decrease its production of _____.

• A) prefrontal cortex; dopamine
• B) hypothalamus; ghrelin
• C) suprachiasmatic nucleus; melatonin
• D) corpus callosum; PYY

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Definitions:

Parietal Pleura

Serous membrane that lines the different parts of the wall of the pleural cavity.

Mediastinum

The central compartment of the thoracic cavity surrounded by loose connective tissue, containing the heart, esophagus, trachea, major blood vessels, and other structures.

Pleural Fluid

The thin layer of fluid between the two pleurae (the membranes surrounding the lungs and lining the chest cavity) that lubricates and facilitates lung movement during breathing.

Inspiratory Muscles

Muscles involved in inhalation, primarily the diaphragm and intercostal muscles, which expand the thoracic cavity.