This article – the second in a six-part series on the gastrointestinal tract – describes the role of the stomach in chemical and mechanical digestion, regulation of hunger, eradication of pathogens ...

Stomach acid, primarily hydrochloric acid, plays a vital role in digestion by breaking down food and enabling nutrient absorption. It acts as a crucial defense against harmful microorganisms, ...

The functions of biomolecules, including lipids, nucleic acids and especially proteins are determined to a great extent by their structure. This structure–function relationship is a foundation of many ...

The esophagus is a tubular, elongated organ that plays an important role in transporting food and liquids to the stomach. Several conditions can negatively affect the esophagus, including acid reflux, ...