Name the structural and functional units of kidneys.

Hint: The structural and functional parts of a kidney are located in its cortex. These units are microscopic and are present in bundles. The main function of these units is to remove all the waste material from the blood that is passing through and excreting it out of the body in the form of urine.

Complete answer:
The structural and functional units of kidneys are nephrons.
A nephron is a microscopic unit of a kidney that facilitates waste removal from the blood.
A nephron consists of two parts mainly – renal tubule and renal corpuscle.

> Renal Tubule
• The renal tubule is a long tube-like structure that is connected to the glomerulus. It consists of three parts:
• Proximal Convoluted Tubule (PCT)
•Loop of Henle
• Distal Convoluted Tubule (DCT)

> Renal Corpuscle
• The glomerulus is a bundle of capillaries that is surrounded by a cup and this structure is called the Bowman’s capsule. The capsule consists of three layers:
• Outer Parietal Layer
• Middle basement membrane
• Inner visceral layer

The nephrons perform ultrafiltration. This process facilitates the movement of water, molecules, and ions from the walls of the capillaries. The ultrafiltrate produced from this process lacks blood cells and large molecules. This liquid passes through the tubes of the nephron and gets collected in the urinary bladder.

Note: The nephrons form a major part of the excretory system. They can be 35 – 55 mm long. The tubules of a nephron also perform absorption/reabsorption of water, glucose, and other essential components needed in the body. The rest of the waste matter that is not absorbed, is excreted out of the body through the urine.