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ANATOMY FOR NURSES [Chap. XVII 



In this chapter we shall devote ourselves to the consideration of 

 the urinary system. 



KIDNEYS 



The kidneys are two compound tubular glands, placed at the 

 back of the abdominal cavity, one on each side of the spinal column 

 and behind the peritoneal cavity. They correspond in position 



to the space included between 

 the upper border of the twelfth 

 thoracic and the third lumbar 

 \ertebra. The right is a little 

 lower than the left in conse- 

 (lucnce of the large space oc- 

 cu])ied by the liver. 



Capsule and supports. — The 

 kidneys are covered by a thin 

 but rather tough envelope of 

 fibrous tissue called the capsule 

 of the kidney, and are usually 

 embedded in a considerable 

 quantity of fat, which, with the 

 assistance of their vessels and 

 the peritoneum, helps to hold 

 them in place. 



Size and shape. — Each kidney 

 is about four inches (100 mm.) 

 long, two inches (50 mm.) broad, 

 one inch (25 mm.) thick, and 

 weighs about four and one half 

 ounces (135 gm.) They are bean-shaped, with the concave side 

 turned toward the spine, and the convex side directed outward. 

 Near the centre of the concave side is a depression called the hilum, 

 which serves as a passageway for the ureter, and for the blood- 

 vessels, lymph-vessels, and nerves going to and from the kidney. 

 Anatomy of the kidney. — If we cut a kidney in two lengthwise, 

 it is seen that the upper end of the ureter expands into a basin-like 

 cavity, called the pelvis of the kidney. This pelvis is irregularly 

 subdivided into smaller, cup-like cavities, called calyces, which 

 receive the pointed projections of the kidney substance. 



Fig. IGG. — Vertical Section of the 

 Kidney. (Collins.) 



