Final answer:
The filtration membrane in the nephron is formed by the glomerulus and the glomerular capsule (Bowman's capsule).
Step-by-step explanation:
The structures that form the filtration membrane in the nephron are the glomerulus and the glomerular capsule (Bowman's capsule). The glomerulus, a tuft of high-pressure capillaries, is fed by the afferent arteriole and drained by the efferent arteriole.
Bowman's capsule surrounds the glomerulus, captures the filtrate from the blood passing through the glomerulus, and funnels it to the renal tubule. The podocytes with their pedicels in the visceral layer of Bowman's capsule and the fenestrated endothelium of the glomerular capillaries create a permeable barrier allowing for the filtration of blood based on particle size.