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- Osmosis
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- The soil water is less concentrated than the cytoplasm of root hairs so water moves into root hairs
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- Dissolved minerals
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- Magnesium
- Calcium
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- Active transport
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- Numerous
- Thin walls
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- Xylem
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- Xylem forms a system of long, narrow, hollow, tubes all the way from the roots to the leaves
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- No
- Root pressure is not even generated in some plants
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- Water entering the root hairs by osmosis happens continuously so the water moves into and up through xylem from the water pushing it from behind
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- Short distance
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- Root pressure is not strong enough to go against the force of gravity in tall trees
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- Henry Dixon
- John Joly
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- Loss of water vapour from the surace of a plant
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- As water is being evaporated out of stomata
- A transpiration stream (stream of water) flows upwards through the plant due to the pulling of the evaporation from the leaves and the chain like structure of the water
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- Water molecules are attracted to other water molecules
- They attach through hydrogen bonds
- This causes a column/chain like structure of the water to form
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- There is a force of attraction between the water molecules and the walls of the xylem
- Water molecules stick to the side of the xylem walls
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- As the water is being evaporated out, it causes a tension (pulling) of the chain of water molecules due to cohesion and adhesion
- IF ASKED TO DESCRIBE THE COHESION TENSION MODEL JUST LIST ALL BULLETED POINTS FROM ABOVE IN THIS ORDER
- Transpiration
- Cohesion
- Adhesion
- Tension
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- High temperature
- Low humidity
- Moderate/gentle breeze
- High light intensity