The bundle of blood vessels located in Bowman’s capsule is called glomerulus. An afferent arteriole from the renal artery enters Bowman’s capsule and divides into a network of 50-60 capillaries to form the glomerulus. Later these capillary networks join to form the efferent arteriole and exit Bowman’s capsule. The diameter of the afferent artery is 50 mm and the diameter of the efferent artery is 25 mm. Due to the difference in the diameter of the two arteries, the blood pressure in the glomerulus is higher. This blood pressure helps in the formation of urine. Glomerulus acts as ultra-filter and causes ultrafiltration.