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

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

Avena curvature test is a bioassay for examining the activity of

• auxins

• cytokinins

• gibberellins

• ethylene.

207.

Gibberellins can promote seed germination because of their influence on

• rate of cell division

• production of hydrolyzing enzymes

• synthesis of abscisic acid

• absorption of water through hard seed coat

Pruning of plants promotes branching because the axillary buds get sensitized to

• ethylene

• gibberellin

• cytokinin

• indole acetic acid.

In a plant organ which is covered by periderm and in which the stomata are absent, some gaseous exchange still takes place through

• aerenchyma

• trichornes

• pneumatophores

• lenticels.

Cork cambium results in the formation of cork which becomes impermeable to water due to the accumulation of

• resins

• lignins

• suberin

• tannins.