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A Handbook of Biology

Renal tubule: It begins with a double walled cup like Bowman’s capsule

which encloses the glomerulus.

Glomerulus + Bowman’s capsule = Malpighian body (Renal corpuscle ).

01

The tubule continues with

proximal convoluted tubule

(PCT), Henle’s loop & distal

convoluted tubule (DCT)

Henle’s loop is hairpin

shaped. It has descending

and ascending limbs

02

The DCTs of many nephrons open into a collecting duct. Collecting duct

extends from cortex to inner parts of medulla. They converge and open

into the renal pelvis through medullary pyramids in the calyces.

The efferent arteriole forms a fine capillary network (peritubular

capillaries) around the renal tubule. A minute vessel of this network

runs parallel to loop of Henle forming a ‘U’ shaped vasa recta.

Malpighian body, PCT and DCT are situated in renal cortex. Loop of

Henle dips into medulla.

03

04

05

TÝPËS ØF ÑËPHRØÑS:

Cortical nephrons (85%): In this, the loop of Henle is short and extends only

very little into the medulla. Vasa recta is absent or highly reduced.

Juxtamedullary nephrons (15%): In this, loop of Henle is long and runs deep

into medulla. Vasa recta is present.

ÜRÏÑË FØRMÅTÏØÑ (PHÝSÏØLØGÝ ØF KÏDÑËÝ)

3 processes: Glomerular filtration, reabsorption & secretion