Tag: water absorption and ascent of sap in plants
Questions Related to water absorption and ascent of sap in plants
Water in plants is transported by or ascent of sap takes place through
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Cambium
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Phloem
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Xylem
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Epidermis
Ascent of sap is
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Upward movement of water in the plant.
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Downward movement of organic nutrients.
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Downward and upward movement of water in the plant.
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Redistribution of inorganic substances in the plant.
- Down to upwards movement is known as ascent and Top to downwards movement is known as descend.
- In plants sap is water and minerals.
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Ascent of sap in the xylem tissue of plants is the upward movement of water and minerals from the root to the top.
The gridling or ringing experiment to prove that the water moves through the xylem vessels was performed by
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Stocking
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Malpighi
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Molisch
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Askenasy
This experiment was introduced by Malpighi in 1675. It involves the removal of a ring of bark (girdle), that is, all tissues outside the vascular cambium. Thus, the correct answer is (B).
The transport of sap from root to top of the plant is
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Ascent of sap
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Conduction
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Transport
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Translocation
When any material movement is from down to upwards it is called as ascending movement.
Sir J.C. Bose proposed a theory of ascent of sap known as
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Pulsation theory
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Transpiration pull theory
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Relay pump theory
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Capillary force theory
Sir J.C. Bose proposed a theory of ascent of sap known as pulsation theory. The pulsation theory states that water is absorbed by the plants due to the metabolic activity of living cells which are in constant state of rythmatic pulsation. But it was not accepted as water can be passively absorbed by the roots even the cells were dead.
Transportation is helpful to plants in
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Cooling
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Loss of excess nutrients
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Upward conduction/ascent of sap
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Loss of excess water
Transportation is the process involving the transfer of materials from one place to another place.
According to the vital force theory, ascent of sap is due to active pulsation of the innermost layer of cortex. This theory was given by
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J. C. Bose
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Dixon
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Strasburger
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Sachs
According to the vital force theory, ascent of sap is due to active pulsation of the innermost layer of cortex. This theory was given by J.C Bose. The pulsation theory states that water is absorbed by the plants due to the metabolic activity of living cells which are in constant state of rythmatic pulsation. But it was not accepted as water can be passively absorbed by the roots even when the cells were dead.
In plants, water moves from
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Less negative to more negative gradient
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More negative to less negative gradient
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Similar gradient
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Zero gradient
The rupture or fractionation do not usually occur in the water coloumn in vessels / tracheids during the ascent of sap because of
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lignified thick walls
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cohesion and adhesion
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weak gravitational pull
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transpiration pull
The rupture or fractionation do not usually occur in the water column in vessels/ tracheids during the ascent of sap because of cohesion and adhesion. This is because continuity of water column is maintained by cohesion and adhesion. The conduction of water from root to aerial parts of plants is called ascent of sap. The water molecules remain attached to each other by cohesion force. The magnitude of this force is very high. This helps in the continuous water column in the xylem. The adhesive force is present between the water molecules and the walls of xylem. This also helps in continuous water column in the xylem.
A column of water within xylem vessels of tall trees does not break under its weight because of
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Dissolved sugar in water
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Tensile strength of water
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Lignification of xylem vessels
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Positive root pressure
The tensile strength of water is its ability to resist the effect of external stress and maintain it's flow. The transpiration all pull exerts great stress on the water column but due to its tensile strength, it doesn't break in between.