Certain substances such as alcohol and aspirin are absorbed by the stomach. But the food products are not absorbed in the stomach. The absorption of the food products, as we'll see in just a moment, takes place in the small intestine. So the stomach serves a purpose in storage as well as in digestion. It typically has a capacity of two liters and is composed of special types of cells that serve several important functions. For example, we have parietal cells that secrete the hydrochloric acid and make our stomach acidic.