Ethylene is an organic compound produced by ripening fruits. In a controlled experiment, researchers found that ethylene gas stimulated the ripening process in newly harvested fruits. Which of the following describes the most likely connection between natural ethylene production and fruit ripening?
(A) As a result of metabolic inactivity, newly harvested fruits are unable to absorb ethylene gas from the atmosphere.
(B) Ethylene gas is a chemical signal through which ripening fruits trigger the ripening process in other fruits.
(C) Because of normal phenotypic variation, only some of the fruits in a given generation are expected to produce ethylene gas.
(D) The rate of ethylene gas production by ripening fruits is an indicator of the relative age of an ecosystem.
Ans: (B) Ethylene gas is a chemical signal through which ripening fruits trigger the ripening process in other fruits.
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