This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Anatomy
[{'content': 'Notochord develops by \nSelect and explain. \nA. 8 weeks of pregnancy, B. 24 weeks of pregnancy, C. 14-21 days post conception, D. 2 weeks post conception', 'role': 'user'}, {'content': 'Answer: C \nExplanation: (C) 14-21 days post conception [Grays40-184; IBS7-47# Genesis of the notochord:> Notochord develops in 3rd week.> Around the 19th day cells that invade into the primitive node region & migrate along the median line cranially from the chordal process (also known as the axial process).> On the 25th day 9 the chordal plate cuts itself off from the endoderm, which then fuses again, & forms a complete cord:# Notochord:> This is in the middle of the mesoderm, between the ectoderm and endoderm, & plays a role in the induction of the neuro ectoblast that lies over it.> Notochord plays a role in the genesis of the vertebral body & becomes the nucleus pulposus in the intervertebral disk', 'role': 'assistant'}]