Читать книгу Developmental Psychopathology - Группа авторов - Страница 61

The process of physical development begins before birth. Soon after conception, the single cell formed by the union of the sperm and egg begins to multiply at a fast pace. Over the course of the following weeks, tissues, organs, and structures begin to form, and the developing fetus takes the shape of a human being. Prenatal development occurs during three phases: the germinal stage (the first two weeks), the embryonic stage (second to eighth week gestation), and the fetal stage (ninth week to birth). Physical development occurs rapidly during the embryonic stage, when most organ systems are rapidly established and a neural tube begins to form, as well as during the fetal stage, during which the remaining organs and extremities continue to mature until birth. During the fetal stage, the fetus begins to move and the sensory systems begin to develop. Around seven months gestation, a fetus is able to respond to sound and light, and by birth, other sensory abilities become fully functional.