Cleavage, morula formation, blastocyst formation, and implantation. Berry’s diagram of the trophoblast differentiating into cytotrophoblast and syncytiotrophoblast is iconic. He also explains ectopic pregnancy clearly. Unit 2: The Embryonic Period (Chapters 5–10) Chapter 5: Second Week – Bilaminar Germ Disc The formation of the amniotic cavity, yolk sac, and connecting stalk. Berry introduces the concept of the prochordal plate —a structure often glossed over in other texts.
A systematic approach to congenital anomalies: malformations, disruptions, deformations, and sequences. Berry discusses critical periods of susceptibility—why the first 8 weeks are most vulnerable to teratogens like thalidomide, alcohol, and retinoic acid. an introduction to embryology by ak berry pdf
The heart is the first functional organ. Berry traces the formation of paired heart tubes, their fusion, and the looping of the heart tube. He emphasizes how septation defects lead to common congenital heart diseases (e.g., ventricular septal defect, tetralogy of Fallot). Unit 2: The Embryonic Period (Chapters 5–10) Chapter
Indifferent gonads, SRY gene action, and the hormonal control of male vs. female duct development. Berry handles sensitive topics like hermaphroditism and testicular feminization with clinical professionalism. ventricular septal defect