MEDICAL BIOLOGY, HUMAN ANATOMY, PHYSIOLOGY AND PATHOLOGY - Ya.I.Fedonyuk 2010

BIOLOGY

SECTION 1. BIOLOGICAL BASES OF HUMAN VITAL ACTIVITY

1.4. ONTOGENETIC LEVEL OF LIFE ORGANIZATION

1.4.3. Biology of Individual Development

Postembryonic period of ontogeny, its periodization

The postembryonic period refers to the period of ontogeny from the moment of birth (or hatching from egg and embryonic membranes) until death. It is divided into three periods: juvenile, mature, and senile. The juvenile period lasts until Puberty; the mature period corresponds to adulthood; the mature period is followed by the senile period, which ends in death. According to another Classification, the postembryonic period is divided into pre-reproductive, reproductive (childbearing), and post-reproductive periods.



Last update: 08/08/2026

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