why hepatic portal vein carries the digested food to the liver as it already contain deoxygenated blood?

Question

do these digested food and deooxygenated blood do not mix one another?

Answer 1

I am uncertain what you are asking here, but veins do not carry food of any sort. 

The hepatic portal vein carries deoxygenated blood as do all veins (except pulmonary veins), from the GI tract and spleen to the liver. This blood is full of nutrients and toxins that the blood has extracted. the liver functions to clear these toxins before the blood is returned to circulate. 

i hope this helps. 

Answer 2

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