ch3 child development

perinatal period

the weeks that precede and follow an infant’s birth, specifically, the period between 22 weeks of gestation and seven days after birth.

prenatal period

the time from conception to birth, divides into three key periods: germinal period, embryonic period, and fetal period

blastocyst

ball of 100 cells that becomes firmly embedded in the lining of the uterus one week after conception; forms a structure with two layers

ectoderm

develops into the nervous system, sensory organs, the nails, teeth, and the outer surface of the skin

mesoderm

develops into muscles, bones, the circulatory system, inner layers of the skin, and other internal organs

endoderm

develops into the digestive and respiratory systems

teratogen

eternal agents that can produce physical malformation and negative psychological and behavioral effects on the developing embryo and fetus