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प्रश्न
How is root hair adapted for the absorption of water from the soil?
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उत्तर
The main root with its many branches form a network in the soil. The root hairs get entangled in the soil particles and remain in close contact with the capillary water surrounding the soil particles. The epidermal cells of root hairs have vacuoles which contain cell sap. Generally, the cell sap is more concentrated than the soil solution. As a result the water enters inside the root hair cells by endosmosis. This water dilutes the epidermal cell sap solution. Then water enters into the cortical cells by osmosis and reaches the endodermal cells and then pericycle cells. From this layer water then enters in the xylem tissue. In this way, the water is absorbed and translocated up to xylem of the root by osmosis.
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संबंधित प्रश्न
the exact location of the Lenticels
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(i) What is the aim of the experiment?
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(iii) What are the results of this experiment?
Root hairs become flaccid, when fertilizers are added to the moist soil around it. Explain.
The alongside diagram A shows a root hair growing through the soil particles. Diagram B is the root hair of an aquatic plant.
(i) Name the parts 1,2,3.
(ii) Name two substances which enter the root hair. What are their uses?
(iii) By what process do these substances enter the root hair?
(iv) Account for the different shapes of root hairs in the two diagrams.
Name the following:
The kind of cells that constitute the cortex of a root.
Multiple Choice Question:
The most widely accepted theory for ascent of sap is ______.
Outer layer of root hair is made up of ________.
Which part of the root helps in the maximum absorption of water and minerals?
They are pipe-like, consisting of a group of specialised cells. They transport substances and form two-way traffic in plants. Which of the following terms qualify for the features mentioned above?
Paheli uprooted a rose plant from the soil. Most of the root tips, with root hairs, got left behind in the soil. She planted it in a pot with new soil and watered it regularly. Will the plant grow or die? Give reason for your answer.
