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What is True statement regarding portal venous system: and explain in detail?
Ans. (a) Whole system is valve lessRef BDC 4th ed. Vol. 11/268-71, Gray's 39th ed /1218-19* In adults, the portal vein and its tributaries have no valves.* In fetal life and for a short postnatal period valves are demonstrable in its tributaries, but they usually gets atrophied.* Rarely some persist in an atrophic form into adulthood.