Question

Thigmotropism is best exhibited by

• A. Tendrils
• B. Stem apex
• C. Root apex
• D. Leaf apex

Answer 1

Answer: (A)

Thigmotropism' also known as 'Haptotropism' term arises from; Thigm+ tropism. 'Thigm' means a touch. 'Tropism' means an orienting response of an organism to the stimulus. 'Thigmotropism' is the directional growth movement which occurs as a mechanosensory response to a touch stimulus. The response exhibited by the organism to the stimulus is mostly involuntary, which means it can go either away or towards from the stimulus of the source as in taxis. The directional response is generally caused by the induction of some pattern of differential growth. The best example is climbing tendrils of the sweet pea when feel the solid object like tree trunk, causes the tendrils to actually attain curvature with that object. Thigmotropism can be positive or negative

So, the correct answer is 'Tendrils'