Botany - Plant Growth and Development Question with Solution | TestHub
Match the column-I and column-II.
| Column-I | Column-II | ||
| (i) | Auxin | (A) | Adenine derivatives |
| (ii) | Gibberellin | (B) | Carotenoid derivatives |
| (iii) | Cytokinin | (C) | Terpenes |
| (iv) | ABA | (D) | Indole compounds |
Options:
Answer:
Solution:
Auxins are weakly acidic growth hormones having an unsaturated ring structure. Indole Acetic Acid (IAA) is the universal natural auxin derived from the precursor amino acid tryptophan with an indole ring structure. Auxins are produced in the stem tip and promotes cell elongation.
Gibberellins are weakly acidic, tetracyclic diterpenes with an ent-gibberelline (gibbane) ring structure formed from the precursors mevalonic acid or acetyl co-enzyme A. Gibberellins causes cell elongation of intact plants and increases the internodal length of dwarf plants.
Cytokinins are plant hormones that are basic in nature and aminopurine (6-amino purine is adenine) or phenyl urea derivatives. Cytokinins promote the cell division or cytokinesis either alone or in conjugation with auxins.
Abscisic Acid (ABA) is a mild acidic dextrorotatory cis sesquiterpene growth hormone formed from the mevalonic acid or carotenoid xanthophylls. ABA acts as a general growth inhibitor by counteracting other hormones like auxins, gibberellins and cytokinins.
