Which Hormone Is Released in Response to Daily Variations in Light

question 65

Multiple Choice

Which hormone is released in response to daily variations in light and tends to rise as night falls, peaks at midnight, and falls again as the sun rises?

• A)adrenaline
• B)thyroxin
• C)melatonin
• D)androgen

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Definitions:

Venous Return

The flow of blood back to the heart through the veins, critical for maintaining cardiovascular function.

Cardiac Cycle

The cardiac cycle is the sequence of events that occurs during one heartbeat, involving the contraction (systole) and relaxation (diastole) of the atria and ventricles to pump blood throughout the body.

Stroke Volume

The volume of blood pumped from the heart's left ventricle per beat.

Cardiac Output

Cardiac Output is the volume of blood the heart pumps through the circulatory system in one minute.