Advertisements
Advertisements
प्रश्न
How does transpiration help the roots absorb water and minerals from the soil?
उत्तर
Transpiration process in plants creates a suction pressure which pulls up water from xylem of the roots to the stem and then to the leaves.
Xylem tissues are in the form of capillary tubes (tracheids and fibres) where narrower the diameter, greater will be the force. Whenever the xylem vessels lay empty, such as during the loss of water by transpiration, the water from below rises into them by a capillary force.
Due to transpirational pull more and more water molecules are pulled up due to their tendency of remaining joined (cohesion). Such pulling force created by the leaves is very important in the case of tall trees where an upward conduction of water takes place.
APPEARS IN
संबंधित प्रश्न
An apparatus as shown below was set up to investigate a physiological process in plants. The setup was kept in sunlight for two hours. Droplets of water were then seen inside the bell jar. Answer the questions that follow:
Why was the pot covered with a plastic sheet?
Stomata of a plant open due to ______.
Boojho wanted to test the presence of starch in leaves. He performed the following steps.
- He took a leaf and boiled it in water.
- He placed the leaf in a petri dish and poured some iodine over it.
He did not get the expected result. Which step did he miss? Explain.
Excessive transpiration is due to ______.
The lower surface of leaf will have more number of stomata in a ______.
Keep some freshly cut flowers in a solution of food colour. Wait for sometime for the dye to rise in the flower, when the stem of the flower is held up in light, coloured strands can be seen inside. Can this experiment demonstrate which tissue is conducting water up the stem?
Plants show temporary and permanent wilting. Differentiate between the two. Do any of them indicate the water status of the soil?
Water molecule is very polar. Polar end of molecule attracts opposite charges on another water molecule (acts like magnet). How will you explain this property of water with reference to upward movement of water? Comment on the upward movement of water given the intermolecular hydrogen bonding in water.
Transpiration occurs:
Define the following term:
Wilting
