Write short note : Types of Nephron. 

Based on location nephrons are of two types $(A)$ Juxta Medullary Nephron

$(B)$ Cortical Nephron.

$(A)$ Juxta Medullary Nephron: It is only $15 \%$ of the total nephron. They are large in size, their loops are connected with vasa recta blood passes through capillaries of glomerulus and than transported by vasa recta of Henle's loop. The loop of Henle is very long and runs deep into the medulla.

$(B)$ Cortical nephrons : The loop of Henle is very short and extends only very little into the medulla. They are $85 \%$ of the total nephron. The efferent arteriole emerging from the glomerulus forms a fine capillary network around the renal tubule called the peritubullar capillaries. A minute vessel of this network runs parallel to the Henle's loop forming a 'U' shaped vasa recta. Vasa recta is absent or highly reduced in cortical nephrons.