Weegy: Transport in plants occurs on three levels:
the uptake and release of water and solutes by individual cells
absorption of water and minerals from he soil by root cells
short-distance transport of substances from cell to cell
[ loading of sucrose from photosynthetic cells into the sieve tube cells of the phloem
long-distance transport of sap within the xylem and phloem
this is a whole plant phenomena - transport of photosynthate from leaf to root
Aquaporins are membrane water channels that play critical roles in controlling the water contents of cells. These channels are widely distributed in all kingdoms of life, including bacteria, plants, and mammals. More than ten different aquaporins have been found in human body, and several diseases, such as congenital cataracts and nephrogenic diabetes insipidus, are connected to the impaired function of these channels ]
(More) 
