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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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In ductus venous, the fetal blood from the placenta reaches to the liver through
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The correct answer is  when there is an increase in placental circulation, to facilitate the rapid transpo of blood through the liver ,a large passage is formed between left umbilical vein and right hepato cardiac channel.This passage is called ductus venosus REFERENCE: TEXTBOOK OF CLINICAL EMBRYOLOGY... VISHRAM SINGH SECOND EDITION....PAGE NO:241