1. Relay pump theory was given by Godlewski in 1884. According to him there was a rhythmic change in the osmotic pressure of the living cells of xylem parenchyma and medullary rays, which brought about a pumping action of water in an upward direction. Ascent of Sap is best explained by 1) Mass (bulk) flow 2) Pulsation Theory 3) Root Pressure 4) Cohesion – Tension Transpiration pull 15.If two solutions have the same osmotic concentration they are said to be 1) Hypertonic 2) Hypotonic 3) Isotonic 4) Hypohypertonic 16. With a decrease in water potential of these living cells water diffuses into them from the adjacent bordering vessels which acted as reservoirs of water. According him the rhythmic changes in the osmotic pressure of living cells of xylem parenchyme are responsible for upward movement of water. Living cells like xylem parenchyma and ray cells remain intimately associated with the vessels and tracheid s. Due to this association many workers thought that ascent of sap was brought about in some manner by the living cells of the stem, although direct evidence in favor of this view was lacking. The largest ‘suction lift’ reported for a man-made device Vital theories 5. According to this theory, the ascent of sap is due to a hydrostatic pressure developed in the roots by the accumulation of absorbed water. Course Hero is not sponsored or endorsed by any college or university. This is presently a widely accepted theory explaining the ascent of sap in plants. The theories are, Vital-Force Theory, Root-Pressure Theory and Physical-Force, With a decrease in water potential of these living cells water diffuses into them from the adjacent. View Answer Answer: Pulsation theory 74 When the plant cells are fully turgid, the turgor pressure is equal and opposite to the The theories are, Vital-Force Theory, Root-Pressure Theory and Physical-Force. Ringing experiment 4. This is followed by an increase in water potential of the living cells and hence the absorbed, water is pumped into the vessel element situated above and the process is repeated again and, again, thus resembling a kind of staircase movement of water in the xylem. The pressure developing in the tracheary elements of the xylem as a result of the metabolic activities of root is referred as root pressure. Vital Theories . The theory was well, Organizational studies and human resource management. Godlewski’s clambering or relay pump theory: Godlewski (1884) suggested that ascent of sap takes place through xylem parenchyma and medullar rays whereas the vessels and tracheids of xylem serve as reservoir. Relay Pump theory (Clambering theory): According to Godlewski (1884) ascent of sap takes place due to rhythmic change in the osmotic pressure of living cells of xylem parenchyma and medullary ray. cording to the ‘Cohesion–Tension’ theory of the ascent of sap, the xylem tension in these situations would be expected to be strongly negative, perhaps fi5tofi20 bars. bordering vessels which acted as reservoirs of water. The pressure developing in the tracheary elements of the xylem as a result of the metabolic activities of root is referred as root pressure. The theory was well, University of Cape Coast,Ghana • MANAGEMENT BUS 406, Sociology A Down To Earth Approach Chap 11-22, University of Cape Coast,Ghana • BUS 406, University of Cape Coast,Ghana • SOC 201, University of Cape Coast,Ghana • LITERATURE 10. The transport system that drives sap ascent from soil to leaves is extraordinary and controversial. These are responsible for bringing about pumping action of water in upward direction. 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