The tendency of a phenomenon to recur at regular intervals; in biological systems, the recurrence of certain activities (including hormonal, cellular, neural) may be annual, seasonal, monthly, daily, or more frequently (ultradian).
    

concept

Der Ablauf des Lebens : Grundlegung zur exakten Biologie / von Wilhelm Fliess.

Photoperiodic regulation of insect and molluscan hormones.

Chronogenetics : the inheritance of biological time / by Luigi Gedda and Gianni Brenci.

Headache and depression : serotonin pathways as a common clue / editors, Giuseppe Nappi [and others].

Die Form des Werdens : eine Kulturgeschichte der Embryologie 1760-1830 / Janina Wellmann.

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Der Ablauf des Lebens : Grundlegung zur exakten Biologie / von Wilhelm Fliess.

Photoperiodic regulation of insect and molluscan hormones.

Chronogenetics : the inheritance of biological time / by Luigi Gedda and Gianni Brenci.

Headache and depression : serotonin pathways as a common clue / editors, Giuseppe Nappi [and others].

Die Form des Werdens : eine Kulturgeschichte der Embryologie 1760-1830 / Janina Wellmann.