Take two similar green leaves. Apply grease on one leaf and leave the other free. Add 1 or 2 drops of acid on each leaf. What kind of change do you observe from this?
A. 1) The leaf to which grease is applied is not effected with the acid. .Inne 2b 16]
2) The leaf to which grease is not applied is effected.
3) From the above activity we can conclude that mucus secreted by the walls of stomach protect it from the harmful effects of hydrochloric acid in the stomach.