Biological Rhythms and Sleep Flashcards
Zeitgeber
Cue that an organism uses to synchronize with its environment
“time-giver”
e.g. the sun
Entrainment
Process of shifting rhythms, synchronizing with a zeitgeber
e.g. being exposed to the sun cycle after not experiencing it for a while
Period
time between two similar points of successive cycles, length of a cycle
e.g. 24 hour sleep-wake cycle
Phase shift
shift in period activity because of a synchronizing stimulus
e.g. jet lag
free-running
organisms maintaining its own cycle without external cues, zeitgeber’s effect is removed
endogenous clock
internal biological clock that drives rhythms with or without external zeitgebers
circadian rhythms
occur around once a day
e.g. sleep cycles
ultradian rhythms
occur more than once a day
e.g. feeding cycles
infradian rhythms
occur less than once a day
e.g. reproductive cycles
Primary zeitgeber for circadian rhythms
light cycles (the sun)
diurnal
active during the light
nocturnal
active during the dark
