Page 6 - LN- EXCRETION

iii. Renal Tubules
Just below the glomerulus, the tubule has a very short neck.
Attached to each Bowman’s capsule is a long, thin tubule with three distinct regions.
These regions are described as follows
(a) Proximal Convoluted Tubule (PCT) Behind the neck, it makes few coils and is restricted to
the cortical region of the kidney.
(b) Henle’s Loop It is quite narrower and U-shaped (or hair pin-shaped) having a descending
limb that ends into the medulla and an ascending limb that extends back from the medulla
into the cortex.
Differences between Descending Limb and Ascending Limb of Henle’s Loop

Note:
* Peritubular Capillary Network (PTCN), is formed when a minute vessel of peritubular
capillaries runs parallel to the loop of Henle forming a U-shaped vasa recta.
* All these capillaries join to form renal venules, which join to form a renal vein that opens
into the inferior vena cava.
Types of Nephrons
Based on the location in the kidney, nephrons are of following two types
1. Cortical Nephrons