Question

explain with examples, the purpose and process of the tubular and vascular elements of the nephron.

Answer 1

Nephron consist of - Vascular struture and tubular structure.

Vascular element - Afferentl and efferent arteriole, Glomerular capillary & vasa recta.

Tubular element - Bowmans Capsule, PCT, LOOP OF HENLE, DCT and Collecting duct

Tubular Process are, Tubular Reabsoption and Tubular secretion.

Tubular Reabsorption : It is the process of absorbing the elements/nutrients/ions from the fitrate back into the blood. It can be active reabsoption occurs in PCT. In PCT most essential nutreint and ions are reabsorbed back into blood.

Tubular section : It is secretion of some ions or metbolites from the vasa recta into the tubular lumen for excreation. e.g. secretion of urea in the ATL, and secretion of K+ & H+ in response to aldosterone.

Vascular process :

filtration - Fliteration of the renal blood occurs in glomerular capillary bed, throgh fenestrate membrane of glomerular capillary and podocytes presnt in the mesnglium. This filtration memebrane allows passage of ion < 7 nm.

Auto Regulation of GFR - Myogenic mechanism helps in mainating the GFR by autoregulation. When renal blood flow increases due to increased BP, it stretches the affrent arteriole which leads to increased calcium influx hence vasoconstrictiona and maintains the GFR.