THE UBINOGENITAL OKGANS.' 



THE urinogenital organs (apparatus urogenitalis) consist of (a) the urinary 

 organs for the excretion of the urine, and (6) the genital organs which are 

 concerned with the process of reproduction. 



THE URINARY ORGANS. 



The urinary organs comprise the kidneys, which secrete the urine; the ureters 

 or ducts which convey it to the bladder, where it is for a time retained; and the 

 urethra, through which it is discharged from the body. 



THE KIDNEYS (RENES) (Figs. 1086, 1088). 



The kidneys are situated in the posterior part of the abdomen, one on each side 

 of the vertebral column, behind the peritoneum, and are surrounded by a mass 

 of fat and loose areolar tissue. Their upper extremities are on a level with the 

 upper border of the twelfth thoracic vertebra, the lower extremity on a level 

 with the third lumbar vertebra. The right kidney is usually on a slightly lower 

 level than the left, probably on account of the vicinity of the liver. In the female 

 the kidneys are a little lower than in the male. The long axis of each kidney 

 is directed from above downward and outward, the transverse axis from within 

 backward and outward. 



Each kidney is about four and one-half inches (11. 5 cm.) in length, two to two and 

 one-half inches (5.5 cm.) in breadth, and about one and one-half inches (3.7 cm.) in 

 thickness. The left is somewhat longer and narrower than the right. The weight 

 of the kidney in the adult male varies from jour and one-half ounces to six ounces 

 (130 to 170 grams); in the adult female, from four ounces to five and one-half 

 ounces (115 to 155 grams). The specific gravity is about 1052. The kidney has a 

 characteristic form, resembling that of a lima bean, and^presents for examination 

 two surfaces, two borders, and an upper and a lower extremity. The combined 

 weight of the two kidneys in proportion to the body iAabout 1 to 240. 



Relations. The anterior surface (fades anterior) of each kidney is convex, and looks for- 

 ward and outward. Its relations to adjacent viscera differ so completely on the two sides that 

 separate descriptions are necessary. 



(a) Anterior Surface of Right Kidney. A narrow portion at the upper extremity 

 is in relation with the suprarenal gland. Immediately below this a large area, 

 involving about three-fourths of the surface, lies in the renal impression on the 

 inferior surface of the liver, and a narrow but somewhat variable area near the 

 inner border is in contact with the second part of the duodenum. The lower 

 part of the anterior surface is in contact externally with the hepatic flexure of the 



1 Usage has sanctioned the employment of urogenital as the equivalent of urinogenital, although the latter 

 form only is philologically correct. 



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