ANATOMY

Detailed explanation-1: -During early development, the kidneys lie close together in the sacral region of the embryo. However, as the abdomen enlarges, the kidneys are drawn apart and ascend to their final position in the lumbar region between weeks six to nine.

Detailed explanation-2: -The area at the center of the kidney. Urine collects here and is funneled into the ureter, the tube that connects the kidney to the bladder.

Detailed explanation-3: -Initially, the ureteric buds are formed at the caudal end of the Wolffian ducts and subsequently the metanephric mesenchyme, induced by the ureteric buds, and the ureteric buds themselves interact with one another to produce the metanephros. The metanephros becomes the permanent kidney.

Detailed explanation-4: -The renal pelvis or pelvis of the kidney is the funnel-like dilated part of the ureter in the kidney. It is formed by the covnvergence of the major calyces, acting as a funnel for urine flowing from the major calyces to the ureter.

Detailed explanation-5: -During development, three successive pairs of kidneys appear: the pronephros, the mesonephros, and the metanephros.