Question

The chemical nature of gibberellins is that they are _____ .
a. Acidic
b. Alkaline
c. Proteinaceous
d. Amines

Answer 1

Hint: Gibberellins are the plant hormones and their function is to control several processes which include cell elongation, germination, flowering, dormancy etc. It is another kind of plant growth hormone.

Complete answer:
- Acidic: Gibberellins are acidic. Due to its acidic nature, it helps in the growth and elongation of the cell. They can energise the rapid growth of roots and stems and can start the mitotic division in the leaves of some plants. It also helps to increase the rates of the germination of seeds.
- Alkaline: The cytokinins are the plant hormones which are alkaline. The most common cytokinin is N 6-isopentenyl adenine. It helps in cell division and cell enlargement. It also helps in the formation of interfascicular calcium and induces secondary growth.
- Proteinaceous: It is present in the plant hormone known as systemin. It helps to signal the defence mechanism of plants to activate chemical defence against herbivores. It was first spotted in the leaves of a tomato.
- Amines: Polyamine is a plant hormone which has an amine nature. It is also a large group of plant hormones which helps in the growth of some plants. It is obtained from the amino acids and is aliphatic amines.
Hence, the correct option is ‘a. Acidic’

Note: More than 100 gibberellins are described from different plants. It is another kind of promotion plant growth regulator.