This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Gynae), Subject name: Gynaecology & Obstetrics
[{'content': 'Weight of placenta at term: \nSelect and explain. \nA. 300 g, B. 500 g, C. 700 g, D. 900 g', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans: b (500 g) Ref: Dutta, 6th ed, p. 29Placenta at term:Diameter: 15-20 cmWeight: 500 gLength of the cord: 50 cmAbout 4/5lhof placenta is fetal in origin.Placenta is a specialized part of chorion. Placenta separates through decidua spongiosum.Blood flow through placenta is 400 ml/min.Terminal villi show a zones for gas exchange and b zones for hormone synthesis.Area of fibrinoid degeneration where trophoblast cells meet decidua is called Nitabuch layer.Note: Nitabuch layer is absent in placenta accreta.', 'role': 'assistant'}]