Biology of Man 493 



bladder where wastes are stored (Fig. 245). Each kidney consists of an 

 outer cortical substance (cortex) and an inner medullary substance (me- 

 dulla). When examined microscopically, the cortex contains numerous 



Renal v:iil^ 



kidney 



Aorta- 



||1_ }»Ascer)d'm(^ vena cava 



BJadder 



Bowman's capsule 



Urethra 



Loop of Heri}e 



rab«?_ 



Fig. 245. — Human urinary system. One kidney has been dissected to show 

 the internal structures. At the right, the details of the blood vessels and the col- 

 lecting tubes are shown. The latter empty the urine into the enlarged end of the 

 ureter which transports it to the bladder. The outer portion of the kidney is the 

 cortical region (cortex) and the inner portion, which contains the numerous glo- 

 meruli and tubes, is known as the medullary region. 



