What are the Physical Features of Kidneys?

Physical Features of Kidneys

Kidneys are a pair of bean-shaped organs located in the abdominal cavity, retroperitoneal space, and posterior to the peritoneum. They extend obliquely from the 12th thoracic vertebra to the 3rd lumbar vertebra. The right kidney is slightly lower than the left kidney due to the presence of the liver on the right side.

External Features

>• Shape: Bean-shaped

>• Color: Reddish brown

>• Size: Approximately 10-12 cm in length, 5-7 cm in width, and 3-5 cm in thickness.

>• Weight: Each kidney weighs approximately 150-170 grams.

>• Location: The kidneys are located in the retroperitoneal space between the peritoneum and the posterior abdominal wall.

>• Hilum: The hilum is a depression on the medial side of each kidney through which the renal artery, renal vein, lymphatic vessels, nerves, and ureter enter and exit the kidney.

>• Renal Capsule: The renal capsule is a tough, fibrous outermost layer that surrounds the kidneys and provides protection and maintains the shape of the kidneys.

Internal Features

>• Renal Cortex: The renal cortex is the outermost layer of the kidney. It contains glomeruli, proximal convoluted tubules (PCT), distal convoluted tubules (DCT), and collecting ducts.

>• Renal Medulla: The renal medulla is the inner part of the kidney, which is divided into pyramids. Each pyramid consists of multiple renal tubules and collecting ducts that converge toward the renal papilla.

>• Renal Papilla: The renal papilla is the apex of each renal pyramid. It contains the openings of the collecting ducts into the minor calyces.

>• Minor Calyces: Minor calyces are small cup-like structures that receive urine from the collecting ducts.

>• Major Calyces: Major calyces are formed by the union of several minor calyces. There are usually 2-3 major calyces in each kidney.

>• Renal Pelvis: The renal pelvis is a funnel-shaped structure formed by the union of the major calyces. It collects urine from the major calyces and directs it to the ureter.

>• Ureter: The ureter is a muscular tube that carries urine from the renal pelvis to the urinary bladder.