In explanation way,....Nephrons are the basic filtering units of kidneys. Each kidney possesses large number of nephrons, approximately 1-1.5 million. The main components of the nephron are glomerulus,

Bowman’s capsule, and a long renal tubule. Functioning of a nephron:

1. The blood enters the kidney through the renal artery, which branches into many capillaries associated with glomerulus.

2. The water and solute are transferred to the nephron at Bowman’s capsule.

3. In the proximal tubule, some substances such as amino acids, glucose, and salts are selectively reabsorbed and unwanted molecules are added in the urine.

4.The filtrate then moves down into the loop of Henle, where more water is absorbed

5.From here, the filtrate moves upwards into the distal tubule and finally to the collecting duct. Collecting duct collects urine from many nephrons.

6.The urine formed in each kidney enters a long tube called ureter. From ureter, it gets transported to the urinary bladder and then into the urethra.

Structure of Nephron

A nephron is the basic structural and functional unit of the kidney. It consists of two main parts: the renal corpuscle and the renal tubule.

Renal Corpuscle

The renal corpuscle is composed of two structures - the glomerulus and Bowman's capsule.

- Glomerulus: It is a tuft of capillaries that filter blood from the renal artery. The glomerulus is surrounded by Bowman's capsule, which collects the filtrate.

- Bowman's Capsule: It is a double-walled cup-like structure that surrounds the glomerulus. The inner layer is composed of podocytes, which are specialized cells that wrap around the capillaries of the glomerulus.

Renal Tubule

The renal tubule is a long and winding structure that starts from the Bowman's capsule and ends at the collecting duct. It is divided into three parts - the proximal convoluted tubule, the loop of Henle, and the distal convoluted tubule.

- Proximal Convoluted Tubule: It is the first part of the renal tubule and is located next to the Bowman's capsule. It is responsible for reabsorbing useful substances such as glucose, amino acids, and ions from the filtrate.

- Loop of Henle: It is a U-shaped structure that is responsible for creating a concentration gradient in the medulla of the kidney. The descending limb of the loop of Henle is permeable to water, while the ascending limb is permeable to ions.

- Distal Convoluted Tubule: It is the last part of the renal tubule and is responsible for fine-tuning the composition of the urine by reabsorbing ions such as sodium and potassium.

Functioning of Nephron

The nephron performs three main functions - filtration, reabsorption, and secretion.

- Filtration: Blood from the renal artery enters the glomerulus, and the pressure forces water and small solutes through the capillary walls and into Bowman's capsule. This process is called filtration and forms the filtrate.

- Reabsorption: The filtrate then moves through the renal tubule, and useful substances such as glucose, amino acids, and ions are reabsorbed into the bloodstream by the cells lining the tubule.

- Secretion: The cells lining the tubule also secrete waste products such as urea and excess ions into the filtrate. The remaining filtrate, which is now urine, moves into the collecting duct and is eventually excreted from the body.

In summary, the nephron is a complex structure that plays a vital role in maintaining the body's homeostasis by filtering the blood, reabsorbing useful substances, and excreting waste products.