Tag: plant growth and development
Questions Related to plant growth and development
In the proms of apical dominance, lateral buds are unable to grow in the presence of apical bud. This is due to
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Less amount of auxin in apical bud
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More amount of auxin in apical bud
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Less amount of cytokinins in lateral buds
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More amount of cytokinins in lateral buds.
To get a carpet like grass, lawns are mowed regularly, this is done to
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Remove the shoot apical meristem
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Remove the axillary buds
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Accelerate the growth of terminal bud
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Both (b) and (c)
The lawn is mowed regularly to remove apical meristem, and prevent vertical growth of the grass and enhance the growth of lateral buds whose growth is hindered due to apical dominance. This helps the grass get a spreading or carpet like appearance.
Removal of auxin source demonstrates that leaf abscission is ........... by auxin, and apical dominance is ............ by auxin.
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promoted, promoted
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inhibited, inhibited
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promoted, inhibited
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inhibited, promoted
The hormone responsible for apical dominance is
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IAA
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GA
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ABA
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Florigen
Indole Acetic Acid IAA is a naturally produced hormone at the shoot tip by the apical bud that results in vertical growth of the stem, however, this inhibits the growth of lateral buds by preventing basipetal transportation of auxin. Which is termed as apical dominance.
Phytohormone A causes apical dominance while phytohormone B overcomes the same. Select the option that correctly identifies A and B.
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A-Auxin, B-Cytokinin
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A-Cytokinin, A-Auxin
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A-Gibberellin, B-Cytokinin
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A-Auxin, B-Gibberellin
Presence of cytokinin in an area causes preferential movement of nutrients towards it. When applied to lateral buds, they help in their growth despite the presence of apical bud. They thus act antagonistically to auxin which promotes apical dominance. Therefore, cytokinin can overcome apical dominance, caused by auxins.
Auxin and cytokinin are antagonistic in which of the following functions?
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Cell division
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Phototropism
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Apical dominance
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Geotropism
Auxins are produced in the apical buds and they inhibit the growth of lateral buds on the stem thus leading to apical dominance. Whereas cytokinins promote the growth of lateral buds over and above the apical buds thereby antagonising the action of auxins.
So, the correct answer is, 'Apical dominance'.
Apical dominance is the function of Auxin.
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True
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False
Apical dominance is the condition in which an apical bud grows taller as compared to the other lateral branches. This is cause because apical bud produces IAA (Indole Acetic Acid) an auxin hormone in abundance. The presence of high concentration of auxin in the apical bud causes the lateral buds to remain dormant. It has been found that if apical bud is removed, the auxin concentration decreases which allows the lateral branches to grow.
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True
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False
Auxins are present in high concentrations in the tip of apical bud and their presence inhibits the growth of lower buds and branches. Thus one shoot becomes the tallest stem and other remain lower. This type of growth shown by apical bud in herbaceous plants is known as apical dominance.
The phenomenon of apical dominance is strenthened by
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Removal of the tiip
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Removal of leaves
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Auxin production
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none of these
Auxin is an important plant hormone with a wide variety of effects. Auxin produced by the apical meristems inhibits the sprouting of lateral buds, and this phenomenon is called apical dominance. Apical dominance refers to an event in which the main stem of the plant grows more dominantly than the other branches on the stems. Production of auxin strengthens the phenomenon of apical dominance. Auxin inhibits the growth of lateral bud, and thereby allow the central stem to grow more vigorously.
Apical dominance means
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Suppression of growth of apical bud by axillary buds .
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Supression of growth of axillary buds by the presence of apical bud.
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Stimulation of growth of axillary buds by removal of apical bud.
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Inhibition of growth of axillary buds by removal of the apical bud.