Life Stages

"The major stages of the human life cycle are defined as follows: • Pregnancy. The development of a zygote into an embryo and then into a fetus in preparation for childbirth. • Infancy. The earliest part of childhood. It is the period from birth through age one. • Toddler years. Occur during ages two and three and are the end of early childhood. • Childhood. Takes place from ages four to eight. • Puberty. The period from ages nine to thirteen, which is the beginning of adolescence. • Older adolescence. The stage that takes place between ages fourteen and eighteen. • Adulthood. The period from adolescence to the end of life and begins at age nineteen. • Middle age. The period of adulthood that stretches from age thirty-one to fifty. • Senior years, or old age. Extend from age fifty-one until the end of life."