d r e a m y
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In translocation, osmotic potential is maintained in the phloem by which process?

More water is moved into the phloem
Sugars move into the companion cells out of the sieve tube element
Sugars are removed at the sink


Could someone help?
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xozxexo
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(Original post by d r e a m y)
In translocation, osmotic potential is maintained in the phloem by which process?

More water is moved into the phloem
Sugars move into the companion cells out of the sieve tube element
Sugars are removed at the sink


Could someone help?
So i asumme you mean water potential when talking about the osmotic potential?

Basically, in translocation sucrose moves into the sieve tube which decreases the water potential. This causes water to flow from the xylem into the phloem to replenish this water potential. This also increases the pressure in the phloem which causes the sucrose to move. The sucrose reaches the sink (root) and is stored in the sink (the sucros has left the phloem)

The osmotic potenial/ water potential would be maintained by the sucrose leaving the phloem. This would increase the water potential in the phloem so water would then move back into the xylem or back into succrounding tissues in the plant.

I hope this helped to explain it
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d r e a m y
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(Original post by xozxexo)
So i asumme you mean water potential when talking about the osmotic potential?

Basically, in translocation sucrose moves into the sieve tube which decreases the water potential. This causes water to flow from the xylem into the phloem to replenish this water potential. This also increases the pressure in the phloem which causes the sucrose to move. The sucrose reaches the sink (root) and is stored in the sink (the sucros has left the phloem)

The osmotic potenial/ water potential would be maintained by the sucrose leaving the phloem. This would increase the water potential in the phloem so water would then move back into the xylem or back into succrounding tissues in the plant.

I hope this helped to explain it
Thank you!!
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Tech1017
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Translocation
• Mass flow from source to sink
• In source/leaf sucrose actively transported into phloem
(ATP against concentration gradient)
• By companion cells
• Lowers water potential of sieve tube cell and water enters by osmosis
• Increase in (hydrostatic) pressure causes mass movement towards sink/root
• In root sugars/sucrose used for respiration or converted to starch for storage
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