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Arrange the following events of mass flow of organic material in sequence I. Sugars are transported from cell to cell in the leaf II. Food is synthesised in form of glucose by leaf cells III. Movement of water takes place into sieve tube elements IV. Downward movement of sugar occurs in the stem V. Solutes are actively transported into the sieve elements |
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a) |
I, II, III, V, IV |
b) |
II, I, V, III, IV |
c) |
II, III, I, V, IV |
d) |
I, II, V, IV, III |
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Arrange the following events of mass flow of organic material in sequence I. Sugars are transported from cell to cell in the leaf II. Food is synthesised in form of glucose by leaf cells III. Movement of water takes place into sieve tube elements IV. Downward movement of sugar occurs in the stem V. Solutes are actively transported into the sieve elements |
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a) |
I, II, III, V, IV |
b) |
II, I, V, III, IV |
c) |
II, III, I, V, IV |
d) |
I, II, V, IV, III |
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(b) According to Munch flow model or pressure flow hypothesis, the correct sequence of transport of organic nutrients from source to sink is that first of all food material synthesis takes place then it is transported from cell to cell in the leaves from leaves cell (mesophyll cell). It is passed into the sieve tube through their companion cells by an active transport Now sieve tube shows high osmotic concentration and absorb water from the adjacent xylem. Having absorbed water, they became turgid and organic nutrients are transported from a region of higher turgor pressure to a region of lower turgor pressure |