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Question
Higher Order Thinking Skill.
There are 3 plants A, B and C. The flowers of A open their petals in bright light during the day but closes when it gets dark at night. On the other hand, the flowers of plant B open their petals at night but closes during the day when there is bright light. The leaves of plant C fold up and droop when touched with fingers or any other solid object.
- Name the phenomenon shown by the flowers of plant A and B.
- Name one plant each which behaves like the flowers of plant A and B.
- Name the phenomenon exhibited by the leaves of plant C.
- Name the plant which behaves like the leaves of plant 'C'?
Solution
- The phenomenon shown by the flowers of plants A and B is photonasty.
- A flower which behaves like the flower of (i) plant A is dandelion and (ii) plant B is moonflower.
- The leaves of plant C exhibit thigmonasty.
- A plant whose leaves behave like those of plant C is Mimosa pudica.
- The plants A and B exhibit the phenomenon based on growth movements.
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RELATED QUESTIONS
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The root of the plant is ______.
- positively phototropic but negatively geotropic
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The petals of the moon flower open up in the morning and close in the evening. This is called photo nasty.
While conducting experiments to study the effects of various stimuli on the plants, it was observed that the roots of plant X grow and bend towards two stimuli A and B but bend away from a third stimulus C. The stem of the plant X however bends ” away from stimulus A and B but bends towards the stimulus C. The stimulus B is known to act on the roots due to factors related to Earth. Keeping these points in mind, answer the following questions:
- What could be stimulus A?
- Name the stimulus seen in B.
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Which parts of a plant exhibit Negative geotropism?
