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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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Cardiac looping in a fetus occurs on:
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The correct answer is  Ans. C. 22-24 days of gestationThe fetal heart development is a sequential process with paired cardiac tubes evident by 18 days of gestation. The two heart tubes fuse to form the primitive heart tube by day 22 of gestation. Cardiac looping usually starts at days 22-24, as the heart tube bends ventrally and towards the right. With looping of the heart tube, the primitive atria moves upwards and towards the back of the ventricles; the primitive ventricle (future left ventricle) comes to the left while the bulbus cordis (future right ventricle) shifts to the right.