Describe the structure of a human kidney | Class 11 Biology Chapter Excretory products and their Elimination, Excretory products and their Elimination NCERT Solutions

Kidneys are reddish brown bean shaped organ situated between last thoracic and third lumbar vertebra. Each kidney has a notch on its inner side called hilum through which ureter, blood vessels and nerved enter. Each kidney is 10- 12 cm long, 5- 7 cm wide and 2- 3 cm thick. It weighs around 120- 170g.

• Inside the kidney there are two zone- outer cortex and inner medulla.

1. Medulla: The medulla is also divided into a few conical masses called medullary pyramids which projects into the calyceas.
2. Cortex: It extends between medullary pyramids and renal column or columns of Bertini.

• Renal pelvis: This is a broad funnel shaped space present inside the hilum.
• Each kidney contains about a million nephrons which is known as functional unit of kidney. Each nephron has two parts: the glomerulus and renal tubules.