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प्रश्न
To which of the following directional stimulus roots of a plant do not respond?
विकल्प
moisture
candle light
touch
gravity
उत्तर
touch
Explanation:
Roots do not respond to touch.
APPEARS IN
संबंधित प्रश्न
Give one example of chemotropism. State whether this example is of positive chemotropism or negative chemotropism.
Plant shoot grows upward in response to ______.
Why is the closing of a dandelion flower at dusk (when it gets dark) not a tropism?
Which of the following plant part exhibits negative phototropism?
(a) root
(b) branch
(c) leaves
(d) stem
P and Q are two types of plants having weak stems which cannot stand upright on their own. The plants P and Q have organs R and S respectively which can grow towards any support which they happen to touch and wind around that support. It is observed that organ R originates from the leaves of the plant whereas organ S originates directly from the stem of the plant.
(a) What is (i) R, and (ii) S?
(b) What is the name of growth movement exhibited by the organs R and S?
(c) Name the stimulus involved in this case.
(d) State whether the behaviour of organs R and S is a tropic movement or a nastic movement.
(e) Name one plant like P and another plant like Q.
A student accidentally places her hand on the flame of the candle and quickly pulls her hand away. The flame represents:
What is a tropic movement? Explain with an example.
When the leaves of the Mimosa pudica plant are touched with a finger, they fold up quickly.
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.
- What could be stimulus-C?
Name a hormone which is responsible for phototropism
