Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
After a storm, sea water floods a field. The next day the crops wilt, even though the soil is wet. Explain what happened.
Osmosis is the movement of water through a selectively permeable membrane towards the side with more dissolved substance. Hypotonic: the cell swells. Isotonic: no change. Hypertonic: the cell shrinks.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The soil water. Sea water has a lot of dissolved salt, so the soil water is now hypertonic to the root cells.
Step 2. Osmosis. Water moves out of the root cells, towards the side with more dissolved substance.
Step 3. Wilting. The cells lose water and are no longer turgid, so the plants wilt.
Answer: the salty soil water drew water out of the roots by osmosis.
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