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Asserion : Long distance flows of photo...

Asserion : Long distance flows of photoassimilates in plants occurs through seive tubes
Reason : Mature seive tubes have parietal cytoplasm and prforated seive plates

A

If both A and R are true and R is the correct explanation of A

B

If both A and R are true but R is not the correct explanation of A

C

If A is true and R is false

D

If both A and R are false

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The correct Answer is:
A
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Assertion : long distance flow of phtoassimilates in plants occurs through sieve tubes. Reason: mature seive tubes have parietal cytoplasm

Assertion : Water and mineral uptake by root hairs from the soil occurs through apoplast until it reaches edodermis. Reason : Mature sieve tubes have parietal cytoplasm and perforated sieve plates.

Identify the statements as true(T) or false(F). A. Xylem fibres are the components of xylem in all categories of vascular plants. B. Advanced angiosperm families like Winteraceae & Trochodendraceae do not have vessals. C. Seive tubes & companion cells are ontogenetically related & are called sister cells. D. The cytoplasm of a mature seive tube occurs in the form of a thin-living layer along the inner side of cell walls.

Assertion (A): Seive tubes are made up of sieve plates that help in conduction. Reason (R): Phloem parenchyma gives mechanical support.

$ Seive tubes in plants are formed of enucleated cells called seive members. ! All the activities of a seive cell are controlled by nucleated parenchyma cells.

(i) In the arrangement shown in the figure, the tank has a large cross section and the pipes have much smaller cross section. The opening at A is unplugged and the water jet hits the ground surface at a horizontal distance x. (a) Find the level of water (h) in the tube B as water flows out of A. (b) Find x. (i) A flat horizontal surface has a small hole at its centre . A circular glass plate of radius R is placed symmetrically above the hole with a small gap h remainng between the plate and the surface A liquid enters the gap symmetrically from all sides and after travelling radially through the gap finally exits from the hole. The volume flow rate of the liquid coming out from the hole is Q (in m^(3)s^(-1) ). (a) If the flow speed just inside the circumference of the circular plate is V_(0) and the speed (V_(x)) of flow inside the gap at distance x(see figure) from the centre of the hole. (b) Write V_(x) in terms of Q, h and x.

TRUEMAN BIOLOGY-Plant Physiology -ASSERTION AND REASON
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  2. [A]: Chlorophylls usually show red fluores- cence though they absorb b...

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  3. Asserion : Long distance flows of photoassimilates in plants occurs t...

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  4. [A]: Rhoea discolor leaves contain anthocya-nin in epidermal cells [...

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  5. [A]: Ringing/Girdling experiments involved removal of all tissues outs...

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  6. [A]: Action spectra for photosynthesis help to identify the pigments i...

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  7. [A] : C3 & C4 cycle can not occur in the same plant [R] : C3 cycle ...

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  8. [A]: Photosynthesis is an oxidation reduction process. [R]: Electron...

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  9. Assertion. Nitrogen deficiency induced purplish colouration in stems, ...

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  10. Asserotion: C(4) photosynthetic pathway is more efficient than the C(3...

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  11. Assertion. The atmospheric concentration of CO(2) at which photosynthe...

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  12. Assertion: Sigmoid growth curve consists of four parts. Reason : La...

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  13. [A] : 2,4-D is a herbicide [R] : It is not used during showing of cr...

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  14. [A] : Nastic movements occur in the directions of stimuls [R] : "Tou...

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  15. [A] : Germinating seeds which store fats as reserve food material are ...

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  16. [A] : Gibberellic acid , when added to isolated aleurone , induce amyl...

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  17. [A] : When apical bud is removed, the next axial bud begins to grow ou...

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  18. [A]: Xanthium will not flower if the long dark period is interrupted b...

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  19. [A]: Senescence is induced by the applica- tion of cytokinin in plants...

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  20. Assertion : A correct concentration of auxin and cytokinin is required...

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