Question

why do an apple turns brown on oxidation​

Answer 1

Answer:

When an apple is cut (or bruised), oxygen is introduced into the injured plant tissue. When oxygen is present in cells, polyphenol oxidase (PPO) enzymes in the chloroplasts rapidly oxidize phenolic compounds naturally present in the apple tissues to o-quinones, colorless precursors to brown-colored secondary products

Answer 2

Answer:

when an apple is cut,oxygen is introduced into the injured plant tissue.when oxygen present in cells(polyphenols oxidase) enzymes in the chloroplast rapidly oxidise phenolic compounds naturally present in the apple tissues to o-quinones , colorless precursors to brown colored secondary products.