ABSTRACT
Origins The ureteric bud and nephrogenic cap are the primordia of the permanent metanephric kidney and its excretory duct, the ureter. At 4 weeks, the R and L mesonephric ducts terminate in the lateral walls of the cloaca (Figure la); at 5 weeks, in the urogenital sinus (Figure lb). In the 5th week, a dorsal outgrowth from the mesonephric ducts, the ureteric bud, grows towards the sacral part of the nephrogenic cord, known as the nephrogenic cap. By their reciprocal interaction during embryonic and fetal life,
• The ureteric bud gives rise to the ureter and distal nephric structures, namely collecting ductules and the terminal ducts (of Bellini), opening into the cal ices and renal pelvis.
