And these integral proteins aid they allow the movement of our ions and molecules across the membrane. So we have two types of movement that takes place inside the proximal convoluted tubial. We have active transport, which utilizes ATP, and we have passive transport which does not utilize ATP. So let's take a look at the following diagram that basically describes several of these epithelial cells binding together to form the membrane the lining of our proximal convolute tubule. So we have these epithelial cells that are connected, and these are our tie junctions that prevent the movement of waste products from the lumen of the proximal convoluted tubule. This is where the filtrate is found to the interstituum of our renal cortex, to these peritubular capillaries that are found within our interstituum.