Besides absorbing what a plant needs from the soil, what other job does a root system do?

توضیح

A root system spreads out through the soil and holds the plant in place against wind and against its own weight, which is a mechanical task quite separate from absorption. The closest rival is the idea that roots push the whole water column upwards, but that column is pulled from the top by evaporation at the leaves, and roots cannot make food at any hour either, because that needs light and the green pigment.