Answer:

Nephrons:

1-Each kidney is formed of millions of small units called nephrons.

2-Nephrons deal with the ultrafiltration of blood.

3-Nephrons are considered the structural and functional parts of the kidney.

Filtration in Nephron:

1-The blood reaches the nephrons through renal arteries.

2-Blood flows in arteries under high pressure.

3-This pressure helps in the filtration of blood through the capillaries which form a network of nephrons.

4-Blood cells and proteins are remains in the capillaries and urea, water and other waste will be removed from the capillaries of nephrons.

5-Sometimes, some useful substances are also removed from the blood along with water.

6-When it reaches the tubular part of nephrons, they are absorbed back by the blood capillaries present in the tubules.