An experimental subject is isolated in an underground room with no windows, no clocks, and no contact with the outside world. Researchers monitoring his behavior observe that he eats breakfast a little bit later each day. What term best describes the subject's biological activity?
A) circadian rhythm
B) free-running rhythm
C) jet lag
D) phase shift
E) entrainment

Question

Quizplus · Accepted Answer

The subject's biological activity is described as a free-running rhythm because it is not influenced by external cues like light or time, causing the internal clock to drift and result in a progressively later schedule.

An Experimental Subject Is Isolated in an Underground Room with No