Endogenous Pacemakers And Exogenous Zeitgebers

Question 1

Endogenous pacemakers

Answer 1

Are internal mechanism that govern biological rhythms
E.g circadian sleep wake cycle.

The main endogenous pacemaker (master clock) is SUPRACHIASMATIC NUCLEUS (SCN) controls other biological rhythms

Question 2

Exogenous zeitgeber

Answer 2

Environmental events that are responsible for resetting the biological clock of an organism

— the SNC contains receptors that are sensitive to light and this external cue is used to syncronise the body’s internal organs and glands