Why is the stomach and intestinal wall not digested ?

Digestion of _ i _begins in the stomach and is completed in the small intestine where it is broken down into _ ii_. The information in which alternative completes the given statement?

How is the small intestine designed to absorb digested food?

In the digestive system, the pH of the stomach and the intestine, respectively are,

The wall of the internal organs such as blood vessels, stomach and intestine contains which type of muscle tissue?

The epithelial tissue that lines the stomach and the intestine is