NEETBotanyPlant - Growth and Development
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): F. Skoog observed that from the internodal segments of tobacco stems, the callus proliferated only if the nutrient medium was supplemented with auxin alone. Reason (R): Miller et al. identified and crystallised the cytokinesis-promoting active substance that they termed kinetin. In the light of the
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A)
- BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
- C(A) is true but (R) is false
- D(A) is false but (R) is true
Correct answer
D. (A) is false but (R) is true
Step-by-step solution
Assertion (A) is false because F. Skoog and his co-workers observed that tobacco stem callus proliferated only if, in addition to auxins, the nutrient medium was supplemented with extracts of vascular tissues, yeast extract, coconut milk, or DNA. Auxin alone was insufficient for callus proliferation. Reason (R) is true as Miller et al. successfully identified and crystallised the cytokinesis-promoting active substance from autoclaved herring sperm DNA and termed it kinetin. Therefore, Assertion is false but Reason