Final answer:
The kidneys are located on either side of the spine, between the T12 to L3 vertebrae, and are protected by multiple layers including ribs, a fibrous capsule, and adipose tissue.
Step-by-step explanation:
The kidneys are vital organs located on either side of the spine within the retroperitoneal space. They are protected by muscle, fat, and ribs. The kidneys are roughly the size of a fist and are well vascularized, receiving about 25 percent of the cardiac output at rest. They are found approximately at the vertebral level of T12 to L3. The left kidney is situated at about the T12 to L3 vertebrae, while the right kidney is slightly lower because it is displaced by the liver. The kidneys are well protected by the eleventh and twelfth ribs, a fibrous capsule, and a layer of fat known as the renal fat pad. Additionally, they are enveloped by a tough renal fascia that helps secure them to the posterior abdominal wall, ensuring they maintain their retroperitoneal position.