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.
B.
growth regulators synthesised by plants and influencing physiological process
Growth regulators are organic substances, other than nutrients, which in low concentration regulate growth, differentiation and development by promoting or inhibiting the same. Phytohormones are growth regulators produced naturally in plants and translocated to another region for regulating one or more physiological reactions when present in low concentration. Phytohormone can have a promoting or inhibiting effect on a process
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
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
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 of the following plant growth regulators (PGRs) promotes root initiation, flowering and induced parthenocarpy?
Gibberellin
Auxin
Cytokinin
Ethylene
Abscisic acid is known as the stress hormone because it
breaks seed dormancy
induces flowering
promotes leaf fall
promotes closure of stomata
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.
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: 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
