Multiple Choice Questions

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Which of the following plant growth regulators (PGRs) promotes root initiation, flowering and induced parthenocarpy?

  • Gibberellin

  • Auxin

  • Cytokinin

  • Ethylene


B.

Auxin

Auxins promote root initiation at a concentration which otherwise is inhibitory for growth of intact root. These are often employed for inducing flowering in litchi and pineapple. Application of auxins to unpollinated pistils make them develop into seedless fruits or parthenocarps.


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Refer the given figures on photoperiodism and select the correct option.

  • A B C
    no correlation between light period and flowering long light- exposure period short light- exposure period
  • A B C
    long light- exposure period no correlation between light period and flowering short light- exposure period
  • A B C
    short light exposure period long light exposure period no correlation between light period and flowering
  • A B C
    no correlation between light period and flowering short light exposure period long light exposure period

Assertion : Vernalization is acceleration of subsquent flowering by low temperature treatment.

Reason : Site of vernalization is apical meristem.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false


Phytohormones are

  • hormones regulating growth from seed to adulthood

  • growth regulators synthesised by plants and influencing physiological process

  • hormones regulating flowering

  • hormones regulating secondary growth.


Assertion: Plant growth as a whole is indefinite.

Reason: Plants retain the capacity of continuous growth throughout their life.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false.


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The cells of the quiescent centre are characterised by

  • having dense cytoplasm and prominent nuclei

  • having light cytoplasm and small nuclei

  • dividing regularly to add to the corpus

  • dividing regularly to add to tunica


Which one of the following methods is commonly used to maintain the genetic traits of a given plant

  • By propagating through seed germination

  • By propagating through vegetative multiplication

  • By generating hybrids through intergeneric pollination

  • By treating the seeds with gamma radiations


Abscisic acid is known as the stress hormone because it

  • breaks seed dormancy

  • induces flowering

  • promotes leaf fall

  • promotes closure of stomata


Assertion: Cytokinins increases shelf life of fruits and vegetables.

Reason : Cytokinins induce cell division.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false


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Dust, oolong and brick are varieties of

  • coffee

  • pepper

  • tea

  • lavang


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