How does ethylene initiate the reaction that converts starch to sugar? ?
After this climacteric, a range of senescence events follow. Enzymes are produced to change the qualities of the fruit. A green (unripe) fruit has a suite of characteristics depending on the species. The skin is green, the fruit is hard, it is loaded with starch, it is acidic, it is odorless. The climacteric respiration increase signalled by ethylene, supports the transcription and translation of genes for hydrolytic enzymes. Some break down chlorophyll, some synthesize anthocyanins, some digest starch into sugar (amylase), some digest pectins (pectinase) that glue the cells together, softening the fruit. Other enzymes convert organic acids into neutral pH compounds (the tartness goes away). The sugar from starch breakdown becomes a solute and water enters the fruit from the xylem. Other enzymes degrade odorless large organic molecules into small aromatic ones. The green, hard, mealy, odorless fruit changes to a bright color, sweet, juicy, soft fruit with a species specific odor. My fa
