What is the significance of juxta glomerular apparatus (JGA) in kidney function? | NCERT solution | Class 11 Biology | Unit-19 Excretory Products and their Elimination



Q.10:- What is the significance of juxta glomerular apparatus (JGA) in kidney function?

 

Answer:

Significance of Juxta Glomerular Apparaus (JGA):



The JGA plays a complex regulatory role. A fall in glomerular blood flow/glomerular blood pressure/GFR can activate the JG cells to release renin which converts angiotensinogen in blood to angiotensin I and further to angiotensin II. Angiotensin II, being a powerful vasoconstrictor, increases the glomerular blood pressure and thereby GFR. Angiotensin II also activates the adrenal cortex to release Aldosterone. Aldosterone causes reabsorption of Na+ and water from the distal parts of the tubule. This also leads to an increase in blood pressure and GFR. This complex mechanism is generally known as the Renin-Angiotensin mechanism.