The cohesion-tension system explains how water moves up the xylem: evaporation from mesophyll cells creates a tension (negative pressure) that pulls a continuous column of water, held together by cohesion (H-bonding) and adhesion to xylem walls, upwards.
<div>- water forms continuous column down the xylem<br> </div><div> - as water evaporates from mesophyll cells</div><div>- more is drawn up the xylem due to cohesion</div><div><div>- water molecules stick together due to hydrogen bonding</div></div><div> - adhesion causes water molecules to stick to xylem walls</div><div>- transpiration pull creates causes tension (negative pressure) in xylem</div><div>- reduces diameter</div>
| Front | Explain the cohesion-tension system in the xylem |
|---|---|
| Back | - water forms continuous column down the xylem - as water evaporates from mesophyll cells - more is drawn up the xylem due to cohesion - water molecules stick together due to hydrogen bonding - adhesion causes water molecules to stick to xylem walls - transpiration pull creates causes tension (negative pressure) in xylem - reduces diameter |
Tags: plant_transport
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