How is the stomach protected from the secretions of its own acids?

CBSE Class 10
, ,
1

How is the stomach protected from the secretions of its own acids ?

  1. Take two similar green leaves.
  2. Grease one leaf with petroleum jelly, leave the other free.
  3. Add 1 or 2 drops of some weak acids on both the leaves.
  4. Observe them after half-an-hour or so and write your observations