Question

ABA (Abscisic acid) is called a stress hormone.

a. How does this hormone overcome stress conditions?

b. From where does this hormone get released in leaves?

Answer 1

a. Role of ABA

Abscisic acid plays an important role in stress conditions. For instance, under conditions where there is a scarcity of water, it causes loss of turgor of the guard cells and it results in the closure of stomata to prevent further water loss through transpiration.

b. Source of ABA

The hormone, abscisic acid is synthesised in chloroplasts and released in the leaves of the plant through the mesophyll cells.