Fertilization takes place when the spermatozoon has successfully entered the ovum and the two sets of genetic material … 展开

The primitive streak, a linear collection of cells formed by the migrating epiblast, appears, and this marks the beginning of gastrulation, which takes place around the seventeenth day (week 3) after fertilization. The process of g… 展开

Following gastrulation, the ectoderm gives rise to epithelial and neural tissue, and the gastrula is now referred to as the neurula. The neural plate that has formed as a thickened plate from the ectoderm, continues to bro… 展开

Organogenesis is the development of the organs that begins during the third to eighth week, and continues until birth. Sometimes full development, as in the lungs, continues after birth. Different organs take part in the development of t… 展开

From the third to the eighth week the face and neck develop.
The inner ear, middle ear and outer ear have distinct embryological origins.
At about 22 days into development, the ectoderm on … 展开

Toxic exposures in the embryonic period can be the cause of major congenital malformations, since the precursors of the major organ systems are now developing.
Each cell of the preimplantation embryo has the potentia… 展开