NEET BIOLOGY

Detailed explanation-1: -ABA is a key hormone that regulates water status and stomatal movement. Under drought conditions, plants produce and accumulate increased amounts of ABA in the guard cells, and this induces stomatal closure to conserve water.

Detailed explanation-2: -Among these, abscisic acid (ABA), is the best-known stress hormone that closes the stomata, although other phytohormones, such as jasmonic acid, brassinosteroids, cytokinins, or ethylene are also involved in the stomatal response to stresses.

Detailed explanation-3: -In response to drought, plants synthesize the phytohormone abscisic acid (ABA) that induces stomatal closure, thereby reducing transpirational water loss.

Detailed explanation-4: -Abscisic acid (ABA) is an important phytohormone regulating plant growth, development, and stress responses.

Detailed explanation-5: -Abscisic acid-induced stomatal closure is mediated by ion efflux from guard cells. Ion efflux in turn leads to osmotic water efflux and a reduction in the turgor and volume of the guard cells, resulting in stomatal closure.