Which of the following studies the prenatal development of sex cells?

Embryology is the branch of biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos and fetuses. Additionally, embryology encompasses the study of congenital disorders that occur before birth, known as teratology.

The study of embryology has a long pedigree. Knowledge of the placenta goes back at least to ancient Egypt, where the placenta was viewed as the seat of the soul. There was even an Egyptian official who held the title "Opener of the Kings Placenta". Furthermore, one Egyptian text from the time of Akhenaten claims that a human originates from the egg that grows in women.

Until the birth of modern embryology through observation of the mammalian ovum by Karl Ernst von Baer in 1827, there was no clear scientific understanding of embryology. Only in the late 1950s when ultrasound was first used for uterine scanning, was the true developmental chronology of human fetus available.