Example emission profiles for CO2 and C2H4 for a ripening tomatoAll fruit produce at least small quantities of ethylene during ripening and the internal ethylene concentrations of non-climacteric fruit varies little during their growth and ripening. Exposing non-climacteric fruit to external concentrations of ethylene can transiently increase their respiration rate proportionally to ethylene concentrations. This transient increase in respiration rate may be evoked more than once but ethylene exposure hastens their senescence, shortening their storage life and potentially causing a loss of eating quality.