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NEET UG BIOLOGY MCQ: PLANT GROWTH AND DEVELOPMENT
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The biological clock measures the length at each night by the
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Correct option: A
Relative amount of red absorbing and far/red absorbing phytochrome present at dawn
Option A is correct because the ratio of red-absorbing phytochrome (Pr) to far-red-absorbing phytochrome (Pfr) at dawn provides information about the length of the night, influencing photoperiodic responses.
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Assertion(A): Dedifferentiated cells can only undergo redifferentiation.
Reason(R): Cork and secondary phloem are the products of differentiation Plants follow …A… pathways in response to environment or phases of life to form different kind of structures. This ability is called …B… Complete the given statement with the correct combination of options Rapid and dramatic increase in shoot length is called Some plants were kept under 15 hours of daylight and 9 hours of night. They started producing flowers. However in some of them night was interrupted by a brief flash of light resulting in failure of flowering to take place. This plant is a- Which of the following statements are fals regarding ethephon?
(A) A source of ethylene.
(B) It is slowly absorbed and transported within the plant to release ethylene rapidly
(C) It causes reduced abscission in flowers anc fruits of cotton.
(D) Supresses the internode elongation in deep water rice plants. Heterophylly can be observed in
I. cotton
II. coriander
III. larkspur
Select the right option
Reason(R): Cork and secondary phloem are the products of differentiation Plants follow …A… pathways in response to environment or phases of life to form different kind of structures. This ability is called …B… Complete the given statement with the correct combination of options Rapid and dramatic increase in shoot length is called Some plants were kept under 15 hours of daylight and 9 hours of night. They started producing flowers. However in some of them night was interrupted by a brief flash of light resulting in failure of flowering to take place. This plant is a- Which of the following statements are fals regarding ethephon?
(A) A source of ethylene.
(B) It is slowly absorbed and transported within the plant to release ethylene rapidly
(C) It causes reduced abscission in flowers anc fruits of cotton.
(D) Supresses the internode elongation in deep water rice plants. Heterophylly can be observed in
I. cotton
II. coriander
III. larkspur
Select the right option