NEET 2014
- Exam
- NEET
- Year
- 2014
- Subject
- Botany
- Chapter
- Plant - Growth and Development
NEET 2014 · Botany · Plant - Growth and Development
Dr F. Went noted that if coleoptile tips were removed and placed on...
Dr F. Went noted that if coleoptile tips were removed and placed on agar for one hour, the agar would produce a bending when placed on one side of freshly- cut coleoptile stumps. Of what significance is this experiment?
Options
- AIt made possible the isolation and exact identification of auxin.
- BIt is the basis for quantitative determination of small amounts of growth- promoting substances.
- CIt supports the hypothesis that IAA is auxin.
- DIt demonstrated polar movements of auxins
Correct answer
D. It demonstrated polar movements of auxins
Step-by-step solution
Darwin and his son observed that the coleoptiles of canary grass responded to unilateral illumination by growing towards the light source. This is called phototropism. They performed series of experiments which concluded that the tip of coleoptile was the site of transmittable influence that caused the bending of the entire coleoptile. F.W. Went isolated auxin from the tips of coleoptiles of oat seedlings and concluded that phototropism of oat seedlings occur. They also concluded that phototropism in the tips of coleoptiles is due to the polar movement of auxin in the stem.
So, the correct answer is 'it demonstrated polar movements of auxins'.