Embryos

Embryos are the very early stage of a fetus, typically lasting up to 8 weeks in humans. They are very important because they form the basis of prenatal development, and have a huge impact on the health of a baby when it is born. Embryos can also be used in medical and scientific research, helping us to better understand the development of a fetus, and to develop new treatments for diseases. Additionally, they are used in fertility treatments, such as in vitro fertilization, which have helped many couples have children that they otherwise wouldn't have been able to.