b. Kidney Tissue. The kidneys are composed of three types of tissue: capsule
tissue, cortex tissue, and medulla tissue. Capsule tissue is tough, white fibrous
connective tissue on the kidney surface. Cortex tissue covers the outer portion of the
kidney. Cortex tissue is firm and reddish-brown in color. Medulla tissue makes up the
masses of collecting tubes, which are the inner portion of the kidneys. The renal
pyramids and papillae are composed of medulla tissue. Cortex tissue extends between
the renal pyramids and the conical masses of tubes in the inner part of the kidneys.
Cortex tissue forms an outer layer on the kidneys and medulla forms inner kidney renal
columns. See figure 1-4.
Figure 1-4. Diagram of a cross section of the right kidney.