CBSE Class 7 Answered

The structure of kidney:

• The kidney is about 11-14 cm in length, 6cm wide and 4cm thick.
• Kidneys have an outer cortex consisting of dark tissues and an inner medulla consisting of lighter tissues.
• A funnel-shaped cavity called the renal pelvis is present on the concave side of kidneys.
• Each kidney is made up of millions of microscopic units called nephrons which deal with the formation of urine from blood.
• Each nephron consists of a cup-shaped structure called Bowman’s capsule, which further divides into a cluster of minute capillaries called glomerulus where filtration occurs.
• Renal arteries supply blood to the kidneys, hence they break into small branches and supply blood to each nephron within which the blood is filtered to remove waste products like urea, uric acid, creatinine, ammonia, salts and water.