Abscisic acid is known as the stress hormone because it
breaks seed dormancy
induces flowering
promotes leaf fall
promotes closure of stomata
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.
A.
If both assertion and reason are true and reason is the correct explanation of assertion
Unlike animals, plants do not stop growing after reaching maturity. They continue to grow and bear new roots, leaves, branches, flowers, etc. While roots, sterns and their branches have indefinite growth, other organs like leaves, flowers and fruits show limited or definite growth. They appear and fall off periodically and sometimes repeatedly.
In lower plants, growth is diffused as every cell can divide and enlarge. Higher plants possess specific areas which take part in the formation of new cells.
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