ANTH 2 Lecture Notes - Lecture 28: Trisomy, Menarche, Ovulation
6 Aug 2020
School
Department
Course
Professor
Document Summary
Different parts of the body mature at different rates. General refers to the body as a whole. The brain is very big at birth (half the adult size) and grows quickly early in life. The reproductive system starts to grow during the teenage years. The adolescent growth spurt in humans is a bump in the height curve and a spike in the height velocity curve. Girls grow differently than boys, they typically stop growing at first menstruation, and boys start later but grow longer males become taller (due to sexual preference) The secular trend in growth: growing and maturing earlier each decade. This could be due to level of nutrition. The declining age of menarche (beginning of menstruation): from 16. 5 (1850) to 12. 5 (today) Birth: 2 million eggs in ovaries; by puberty, 400,000. Atresia: egg cell death rate increases at 40, resulting in end of ovulation by.
