The lower GI tract is the lower part of the digestive system, responsible for crucial roles in digestion, nutrient absorption, and waste elimination.| Guts UK
The upper gastrointestinal tract is the top part of the digestive system, responsible for the vital roles of initial digestion and absorption of nutrients.| Guts UK
The digestive system is made up of a series of organs, responsible for breaking down food and liquids into smaller molecules that the body can use for things such as energy, growth and repair.| Guts UK