Answer:
Different researchers break the life cycle of humans into different number of stages. The life cycle of the humans can be categorized into:
Pregnancy: During pregnancy, an embryo is formed from a zygote. Then, eventually a fetus is formed.
Infancy: Infancy can be described as the earliest period after a child is born.
Childhood: The age where the child starts to learn from his environment.
Puberty: The beginning of adolescence is known as puberty. It is the time when various hormonal changes occur.
Adolescence: The late teen ages.
Adulthood: The age when the person has passed the teen ages.
Old age: People above the age of fifty.