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AQA Biology

Megster8

What is the difference between root pressure and transpiration pull?

(edited 9 years ago)

Reply 1

zed963

Original post by Megster8

What is the difference between root pressure and transpiration pull?

Transpiration pull is the continuous flow of water from the xylem to the leaf.

As the water evaporate or transpires from the leaf, it can create a low water potential and so water moves from high water potential in the xylem to a low water potential in the leaf.

Root pressure is when the root pumps in ion to lower the water potential in the "cytoplasm" so that water can move in from surrounding soil and will move by osmosis down a water potential gradient. This keeps happening and can either go through the apoplastic pathway or the symplastic pathway.