During filtration, anything that is small enough to pass through all three layers of the filtration membrane will become part of the filtrate. sometimes, the least porous layer of this membrane becomes clogged and then glomerulonephritis may occur. what is the name of the most porous layer of the filtration membrane? a. fenestrated endotheliumfb. iltration slitsc. capsular epitheliumd. visceral epithelium