Our tendency to feel wakeful and sleepy on a 24-hour basis depends mainly on
a. a cycle generated by a mechanism in the brain
b. our perception of environmental stimuli such as heat and light
c. a cycle generated by hormone-producing organs such as the adrenal gland
d. wear and tear on the muscles followed by a period of repair
I chose answer A. because humans have mechanisms that prepare us for activity during the day and sleep at night. But the other choices seem to somewhat fit...Is this answer correct?
I agree that A is the best answer. However, we can modify the brain mechanism by external stimuli.
Yes, your answer A is correct. Our tendency to feel wakeful and sleepy on a 24-hour basis primarily depends on a cycle that is generated by a mechanism in the brain. This mechanism is known as the circadian rhythm, which is essentially an internal biological clock that regulates various physiological and behavioral processes over a 24-hour period.
The circadian rhythm is influenced by various factors, including both internal and external cues. Internal cues include the release of certain hormones in the body, such as melatonin, which helps promote sleep. External cues, on the other hand, include environmental stimuli like heat and light, which can also affect our state of wakefulness or sleepiness.
However, while choices B, C, and D are related to sleep and wakefulness, they are not the primary factors that determine our 24-hour cycle. The perception of environmental stimuli, such as heat and light, may be secondary influences on our sleep-wake cycle but are not the underlying mechanism. Similarly, hormone-producing organs, such as the adrenal gland, do play a role in regulating sleep and wakefulness, but they are not the main driving force behind the 24-hour cycle. Lastly, wear and tear on the muscles and subsequent repair are not directly related to our sleep-wake cycle.
Therefore, in terms of which choice best describes the primary factor for our wakeful and sleepy tendencies on a 24-hour basis, choice A, a cycle generated by a mechanism in the brain (specifically the circadian rhythm), is the most accurate answer.