Give examples of rhythmic processes in the plant and animal world.

Rhythms in plants have a number of periods. For example, some stems have a growth period of less than one hour, but some bamboos have a flowering period of seven years. The most common rhythms are those with a period of about twenty-four hours, called circadian rhythms. Some examples of processes that show circadian rhythms are photosynthesis, stomatal movements, root pressure, nitrogen fixation, bioluminescence, cell division, leaf movement, flower opening, and scent emissions. Circadian rhythms are ubiquitous in many organisms. Animals that are forced to work actively around the clock usually show reduced productivity, health and survival. The circadian clock coordinates physiological and biochemical processes in the body, functions as a reference to time (for example, for the orientation of the solar compass and memory of time space), allows organisms to predict fluctuations in their environment, and is the basis for the transduction of seasonality from the photoperiod.