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1) Explain why a high concentration of salts in the soil tends to reduce transpiration.

2) explain why seedlings have a better chance of survival when transplanted in the evening.

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Answer:

The absorption of water by the roots of plants is through the osmotic gradients between the soil and the plants xylem vessels.

The high the osmotic gradients the faster the water uptake though the sieve tubes in the plants. The movement of water from the soil into the roots is by osmosis and root pressure.

In a normal soil Osmosis is the movement of water molecules from the region of higher water potential(soil) to the region of lower water potential(plant roots) though a semipermeable membrane.

Therefore a soil with high salt concentration the higher salt would affect the osmotic potential and few water molecules would be able to move from the roots into the roots. This is because the more salt molecules reduced the water potential for water molecules to move through the root by the root pressure initiated by osmosis to form transpiration pull and stream in stems.

Since the loss of water in transpiration comes from water absorbed by the roots through osmosis, root pressure ,transpiration stem and pull, ,the reduced absorbed water leads to reduced transpiration.

2.

The loss of water from the leaves is through stomata. These are usually open for water loss by transpiration .During evening they are close. Therefore transpiration stream amd pull do not take place, so little water absorbed from the soil and water s conserved in plants.

Thus transplant done during the evening gives the seedlings chances of survival because the closed stomata ensues waters conservation, and less stress on the roots which prevent transpiration through the stomata..

Step-by-step explanation:

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