PSY210H5 Chapter Notes - Chapter 3: Motor Coordination, Toxoplasmosis, Muscle Tone
Document Summary
Babies are prone to many negative effects: maternal age, parity (whether a mother had a child before), medication/diagnostic procedures. Conception occurs during period of woman"s ovulation: egg that is released from the mother"s ovaries lives to about 3-5 days. Prenatal development : 38 weeks (9 months) Pregnancy occurs in 3 trimesters (three periods of 3 months) Travels through fallopian tubes and implants itself to uterus" wall. Zygote"s stems penetrate uterus wall"s blood vessels; making the zygote physiologically dependent on mother. Period of rapid growth starting from 3rd week of gestation. Embryo develops three layers: ectoderm: skins outer layer, hair, nails, teeth, nervous system, mesoderm: skin"s inner layer, muscles, skeleton, circulatoy/excretory system, endoderm: gi tract, trachea, bronchi, eustachian tubes, glands, & pancreas/liver. Period prone to congenital anomalities due to environmental assaults: neural folds close in 4th week of gestation, however if it fails to close child will develop spina bifida (spinal cord & membranes will protrude from spinal column)
