Final answer:
The right kidney is positioned lower than the left to accommodate the liver. Protected by the ribs, fat, and a fibrous capsule, the kidneys sit retroperitoneally in the abdominal cavity.
Step-by-step explanation:
Kidney Position and Anatomy
The right kidney is slightly inferior to the left kidney, a positioning that accommodates the liver. This organ displacement is necessary because the liver, which is located in the upper right quadrant of the abdominal cavity, is quite large and would otherwise compress or displace the right kidney. Anatomical illustrations, such as Figure 19.3.2, demonstrate that the kidneys are retroperitoneal and are located high in the back of the abdominal cavity, with the left kidney being slightly larger due to its position on the left side, away from the liver.
Each kidney is encapsulated by a fibrous capsule and surrounded by a shock-absorbing layer of adipose tissue called the renal fat pad, further encased by the renal fascia. These together protect and maintain the structure of the kidneys.
The right kidney's inferior position is attributed to the presence of the liver just above it, necessitating this slight anatomical adjustment. The anatomy of the kidneys is closely associated with function, and their well-vascularized nature indicates their importance in filtering blood. Each kidney receives about 25 percent of the cardiac output at rest.