Now, for the case of dipeptides and tripeptides, instead of using the sodium dependent system, we use a hydrogen ion dependent cotransporter system and we'll see exactly what that means in just a moment. So basically, in this system, we have to use a hydrogen sodium exchange system, where we establish a proton gradient, a hydrogen ion electrochemical gradient, and we use that gradient to basically transport the dipeptides and tripepptide. So, to see exactly what we mean, let's look at the following diagram. So, let's suppose our digestive enzymes found on the brush border break down the small peptides into tripepptides, dipeptides and amino acids. Let's begin by focusing on only the amino acids. So before the amino acids actually travel into the cytoplasm of our cells.