Question

explain the functions of different tubules of nephron

Answer 1

Renal tubules are essential structures in the kidneys. This lesson explores the function of the renal tubule and its parts, including the proximal and distal convoluted tubules, the loop of Henle, and the collecting duct. Learn how these components work together to absorb materials and form urine.

Answer 2

Answer :

There are 4 tubules in a nephron :

1. PCT
2. Henle's Loop
3. DCT
4. Collecting Duct

PCT :-

• It is also called Proximal Convulated Tubule.
• It is lined by simple cuboidal epethelium cells.
• It helps in increment of surface area which in turn helps in more reabsorption.
• PCT absorbs essential nutrients and 70-80% of electrolytes and water.
• It helps to maintain pH.
• It helps to maintain ionic balance of the body fluids.
• This is done by selective secretion of certain ions like potassium ions and hydrogen ions, along with ammonia; into the filtrate.
• Also, by absorption of HCO3 ion.

Henle's Loop :-

• Here, minimum minimum reabsorption occurs.
• This region helps in maintaining high osmolarity of medullary interstitial fluid.
• The descending limb of henle's loop is permeable to water but impermeable to electrolytes.
• The ascending limb of henle's loop is permeable to electrolytes but impermeable to water.
• The concentrated filtrate when passes upwards in the henle's loop it gets diluted because of the passage of electrolytes to the medullary fluid.

DCT :-

• It is called as distal convoluted tubule.
• It helps in reabsorption of sodium ions and water.
• It is also capable of reabsorption of HCO3 ions.
• Also, it can selectively secrete hydrogen and potassium ions also NH3 to maintain the pH and balance sodium potassium in the blood.

Collecting Duct :-

• This is a long duct which extends from cortex of the kidney to the inner part of the medulla.
• Large amount of water can be reabsorbed here.
• This region also allows passage of small amounts of urea in Mercury interstitium.
• It helps in the maintenance of PH and ionic balance of blood by selectively secreting hydrogen ions and potassium ions.