Biology
Water transport in plants
How water travels from the roots all the way up to the highest leaves, without any pump.
A large tree can be many meters tall. Even so, the water from the soil reaches the topmost leaves, although the plant has no heart and no pump. How this works is one of nature's most elegant solutions.
The root takes up water
Everything starts underground. The root has fine root hairs that greatly increase its surface. Through these hairs the plant draws water out of the soil, and along with the water it takes in dissolved that it needs to grow.
Vessels as water pipes
Inside the stem and the trunk lie thin tubes called vessels. Like a network of pipes they run from the root into every leaf. Inside them the water rises as a single unbroken column and carries the dissolved minerals along with it.
Evaporation pulls the water up
The engine sits at the top in the leaves. Through tiny openings on the underside of the leaf, called stomata, water constantly evaporates into the air. Because the column of water holds together, every evaporating particle pulls water up from below. In this way the whole column is drawn upward bit by bit.
Why the water does not break apart
Water particles cling to each other like tiny magnets. This attraction keeps the column of water in the vessels from breaking, even when it is pulled hard from above. That is why the water can make the whole trip upward even in a tall tree.
Exercises
0 of 6 solvedTime to try it yourself. You can't break anything, every attempt counts.
Through which part does the plant take up water from the soil?
What mainly drives the water transport upward?
A tree is 12 meters tall. How many meters does the water rise from the ground up to the topmost leaves?
Put the path of the water through the plant in the correct order, from bottom to top.
- 1the water rises up through the vessels in the stem
- 2the root takes up water from the soil
- 3the water reaches the leaves
- 4the water evaporates from the leaves into the air
A plant takes up 2 liters of water a day. How many liters is that in 3 days?
Match each part of the water transport to its job.