Both serving much the same purpose in nutrient absorption and\or use. Many tout plant nutrition only, AND ideally, I concur as the WORK has been done for us and the nutrition is better assimilated. I say ideally, because as you know plants world wide are very nutrient poor and\or loaded with pollutants like everything else and there is no such thing today.
The inside out root design of the animal intestine can, and does perform the same function of the plant root where the body can and does uses\takes what it needs to make anything it may be lacking just as a plant does, and of course discards the rest.
When we are sick and diseased, that is why juicing is so beneficial... it gives our body vital nutrition without the intense required work.