When the first astronauts travel to Mars,they will be traveling for long periods of time with no external time cues.You would predict that the circadian rhythms for these astronauts would
A) drift toward a slightly longer cycle.
B) drift toward a slightly shorter cycle.
C) stay synchronized with a 24-hour cycle.
D) become sporadic and show no definite pattern.

Question

Quizplus · Accepted Answer

Circadian rhythms, which are regulated by the suprachiasmatic nucleus in the brain, typically have a slightly longer cycle than 24-hours when no external time cues are present. This is known as free-running, and it is likely to occur when astronauts are traveling to Mars and experiencing prolonged periods of darkness and isolation.

When the First Astronauts Travel to Mars,they Will Be Traveling