The Human Embryo
In the United States alone there is an average of about four million people born every year (http://www.cdc.gov/nchs/releases/02news/womenbirths.html). In a normal pregnancy the human embryo goes through a very complicated process. During the nine months of pregnancy the embryo develops all the basic things, such as the heart, liver, and brain, that it needs to live in the outside world.
A nine-month pregnancy is divided, by doctors, into three trimesters of equal length. During each trimester the baby goes through different developments and continues to grow. …
