BIOL130 Lecture Notes - Lecture 1: Endomembrane System, Transfer Rna, Threonine
You are an amino acid in the lumen of the small intestine from a recently digested protein meal, faced with a wall of intestinal epithelial cells. You have always been intrigued by the idea that cells had their own digestive systems. Your ambition is to be incorporated into a lysosomal enzyme within one of those intestinal epithelial cells. They protect our body by being a barrier between our internal cells and the dirt and microbes in the environment. Once we swallow that bite of food, it travels down a path lined with epithelial cells. When it gets to our intestines, another set of epithelial cells absorbs and transports nutrients from the foods we eat and helps process it for energy the body can use. So the goal of the amino acid is to get from the lumen of the intestines to the internal environment of the epithelial cells.