State two roles of transpiration in nutrient uptake

Transpiration is the key process that powers the uptake and movement of dissolved minerals from the soil throughout the plant. It plays two main roles:

1. Transpiration Pull: When water evaporates from the leaves through tiny pores called stomata, it creates a suction force (negative pressure) in the xylem vessels. Because water molecules stick together (a property called cohesion), this pull drags the entire column of water — along with dissolved minerals — upward from the roots to the leaves. This steady movement ensures that nutrients reach even the tallest parts of the plant.

2. Mass Flow of Minerals: The transpiration pull also drives the large-scale (bulk) flow of water and nutrients through the xylem. As water is lost from the leaves, more water enters the roots to replace it. This incoming water carries dissolved minerals from the soil, ensuring a constant supply of essential nutrients to all parts of the plant — especially growing tissues like new leaves, buds, and roots.