Abscisic acid is known as the stress hormone because it

• breaks seed dormancy

• induces flowering

• promotes leaf fall

• promotes closure of stomata

Dust, oolong and brick are varieties of

• coffee

• pepper

• tea

• lavang

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

• Gibberellin

• Auxin

• Cytokinin

• Ethylene

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: 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.

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

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

98.

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.

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

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