Question

In the pressure flow hypothesis osmotic pressure at sink must be?

Answer 1

Pressure flow hypothesis:

1. Pressure flow hypothesis states that the water containing food flows through the phloem under pressure.
2. This pressure is created by the difference in the content of water in the phloem and xylem.
3. As the sugar is transported from the leaves by active transportation into the phloem, the water entered the phloem from the nearby xylem by the process of osmosis.
4. This leads to the increase in the osmotic pressure of the phloem.
5. As the phloem sap moves down from the leaves, the sugar is absorbed by the stem and roots of the plants thus, removing the sugar from the phloem.
6. When the sugar is removed at the sink, the osmotic pressure of the phloem decreases.