The bladder can distend to store urine that eventually leaves through the urethra . Human excretory system and the details of the kidney. Images from Purves et al. The nephron consists of a cup-shaped capsule containing capillaries and the glomerulus , and a long renal tube . Blood flows into the kidney through the renal artery, which branches into capillaries associated with the glomerulus.
Arterial pressure causes water and solutes from the blood to filter into the capsule.
Fluid flows through the proximal tubule , which include the loop of Henle , and then into the distal tubule . The distal tubule empties into a collecting duct. Fluids and solutes are returned to the capillaries that surround the nephron tubule. Filtration of the blood in the fine structure of the kidneys. Image from Purves et al.