ethylene

(noun)

a plant hormone that is involved in fruit ripening, flower wilting, and leaf fall

Related Terms

Examples of ethylene in the following topics:

  • Abscisic Acid, Ethylene, and Nontraditional Hormones

    • Ethylene is associated with fruit ripening, flower wilting, and leaf fall.
    • Ethylene is unusual because it is a volatile gas (C2H4).
    • These effects were caused by ethylene volatilizing from the lamps.
    • Ethylene stimulates the conversion of starch and acids to sugars.
    • Ethylene is widely used in agriculture.

  • Properties of Alkenes

    • Large amounts of ethylene are produced from natural gas via thermal cracking.
    • A space-filling model of ethylene, the simplest alkene, showing its planar structure.

  • Elimination Reactions

    • An industrial preparation of vinyl chloride from 1,2-dichloroethane, made by adding chlorine to ethylene, proceeds by elimination of a chlorine atom from an intermediate carbon radical.

  • Writing Formulas for Polymeric Macromolecules

    • Here ethylene (ethene) is the monomer, and the corresponding linear polymer is called high-density polyethylene (HDPE).
    • This polymer is called polyethylene rather than polymethylene, (-CH2-)n, because ethylene is a stable compound (methylene is not), and it also serves as the synthetic precursor of the polymer.

  • Ziegler-Natta Catalytic Polymerization

    • In the case of ethylene, rapid polymerization occurred at atmospheric pressure and moderate to low temperature, giving a stronger (more crystalline) product (HDPE) than that from radical polymerization (LDPE).

  • Nomenclature

    • Examples are: CH3CH2OCH2CH3, diethyl ether (sometimes referred to as ether), and CH3OCH2CH2OCH3, ethylene glycol dimethyl ether (glyme).

  • Reactions of Epoxides

    • The aqueous acid used to work up the third reaction, following the Grignard reagent cleavage of the ethylene oxide, simply neutralizes the magnesium salt of the alcohol product.

  • Addition by Electrophilic Reagents

    • This is seen in the ionization potentials of ethylene and acetylene.
    • Since pi-electrons are less tightly held than sigma-electrons, we expect the ionization potentials of ethylene and acetylene to be lower than that of ethane, as is the case.
    • Gas-phase proton affinities show the same order, with ethylene being more basic than acetylene, and ethane being less basic than either.

  • Vitamins and Amino Acids

    • While in plants, 1-aminocyclopropane-1-carboxylic acid is a small disubstituted cyclic amino acid that is a key intermediate in the production of the plant hormone ethylene.

  • Plant Responses to Wind and Touch

    • Ethylene and jasmonate are likely involved in thigmomorphogenesis.