All the blood in the body pass through the kidneys several times in a day. As they filter it they remove the waste as urine which then passes from the kidney where it collects in the renal pelvis. It then moves to the ureters which send it to the urinary bladder and then through the urethra as it is passed out of the body in a process known as urination.

There are about a million microscopic filters for the blood called nephrons in each kidney which filter the blood. Some of the structures that allow the kidneys to perform, these functions are part of the gross anatomy (can be seen with the naked eye), others are microscopic anatomy (can be seen when observed under a microscope only). Together these structures work to allow the body to maintain homeostasis and general good health.

Gross Anatomy of the Kidneys: The main components of the gross anatomy of the kidneys are as follows in this list:

• Renal cortex

• Renal papilla

• Renal medulla

• Renal capsule

• Minor calyx

• Major calyx

• Renal column

• Renal pyramid

• Renal pelvis

• Ureter

Homeostasis is when the body is in a state to maintain internal stability, even when the environment around it changes. In a state of homeostasis, the body is able to detect harmful changes in its’ environment and activate mechanisms that counteract them. If the body loses its’ ability to maintain homeostasis, the result is usually disease or death.

The process of separating and eliminating the wastes from the body’s fluids is called excretion. The kidneys are the main organs in the urinary system responsible for excretion. The other excretory systems include the respiratory system, the integumentary system, and the digestive system. The urinary system excretes a wide variety of metabolic wastes, toxins, drugs, hormones, salts, hydrogen irons, and water.