👉 Ontogenesis, also known as developmental biology or epigenetics, refers to the study of how genes and other molecular factors influence the development of an organism from its embryonic stage into adulthood. The term "ontogenesis" is derived from the Latin word "ontogenus," meaning "from the embryo." This term applies to all stages of life, including infancy, childhood, adolescence, young adulthood, and old age, as well as developmental disorders such as cancer and Alzheimer's disease.