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phloem help please

"At the respiring cells, there is a low sucrose content so sucrose is actively transported into them from the sieve tubes"

Why is this active transport if there is a conc gradient?
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eupheme
10
If there was no active transport you would end up with an equilibrium being established with an equal concentration of sucrose in sink cells and phloem.

More sucrose needs to be taken up so that water potential increases and water returns to the xylem by osmosis. This lowers the pressure at the sink and maintains the hydrostatic pressure gradient so that translocation of sugars from source to sink continues.
ah okay thanks!
Original post by rumaisa_
If there was no active transport you would end up with an equilibrium being established with an equal concentration of sucrose in sink cells and phloem.

More sucrose needs to be taken up so that water potential increases and water returns to the xylem by osmosis. This lowers the pressure at the sink and maintains the hydrostatic pressure gradient so that translocation of sugars from source to sink continues.

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