AP BIOLOGY

Detailed explanation-1: -The gaseous hormone ethylene plays a key role in plant growth and development, and it is a major regulator of stress responses. It inhibits vegetative growth by restricting cell elongation, mainly through cross-talk with auxins.

Detailed explanation-2: -Ethylene is different from non-gaseous hormones in several ways. Ethylene moves within the plant by diffusion and is thought to be synthesized at or near its site of action, similar to the gaseous signal nitric oxide in mammals.

Detailed explanation-3: -Ethylene is regarded as a multifunctional phytohormone that regulates both growth, and senescence. It promotes or inhibits growth and senescence processes depending on its concentration, timing of application, and the plant species.

Detailed explanation-4: -Ethylene is a colorless gas at room temperature. At very low temperatures it is a liquid. It is used as a refrigerant and in welding and cutting metals. It is also used to manufacture Ethylene Oxide, Mustard Gas and other organics, and to accelerate the ripening of fruits.