It is able to effectively anticipate transitions of light and dark phases by using a circadian clock.

Subjects are thus forced to live by their internal circadian "clocks".

Along with corresponding messages from the circadian clock, this tells the body it needs to sleep.

The circadian clock also gives the time for the onset of labour.

This is one version - there are several - of what the circadian clock looks like at the most fundamental level.

Under these circumstances, the circadian clock alone modulates the body's biological rhythms.

Therefore, a cell's circadian clock may play a large role in its likelihood of developing into a cancer cell.

Due to the circadian clock, sleepiness does not continuously increase as time passes.

Time cues keep the normal human circadian clock aligned with the rest of the world.

Smith believes his work will interest athletes interested in wise use of the circadian clock.