Question

Which among the following hormones is toxic to plants in large concentrations, regulates protein synthesis and causes bud formation and root initiation?

• A. Ethylene
• B. Auxin
• C. Cytokinin
• D. Gibberellins

Answer 1

The correct option is B Auxin

• Auxins are a group of hormones that positively influence cell enlargement, bud formation, and root initiation.
• In conjunction with cytokinins, they control the growth of stems, roots, and fruits, and convert stems into flowers. Auxins were the first class of growth regulators discovered.
• They affect cell elongation by altering cell wall plasticity. Auxins act to inhibit the growth of buds lower down the stems, and also to promote lateral and adventitious root development and growth.
• Leaf abscission is initiated by the growing point of a plant ceasing to produce auxins. Auxins in seeds regulate specific protein synthesis, as they develop within the flower after pollination, causing the flower to develop a fruit to contain the developing seeds.
• Auxins are toxic to plants in large concentrations, they are most toxic to dicots and less so to monocots.

Therefore, the correct answer is option B.