The renal system is a group of organs that work together to produce, store, and release urine. Urine is the liquid waste material excreted from the body. The organs that work together in this system include the kidneys, bladder, ureters, and urethra. It is also known as the urinary or the excretory system.
The kidneys are a vital part of the renal system. They are located in the back portion of the abdominal cavity, with one on either side. Perhaps the most well-known function of the kidneys is to transport urine into the tubes known as ureters before it exits the body. These organs also have several other important functions, however, such as helping to regulate blood pressure. They also work to regulate the pH balance in the human body as well as the balance of electrolytes such as sodium and potassium.
The next part of the system is the bladder, sometimes referred to as the urinary bladder. The bladder is shaped much like a muscular, hollow balloon and sits in the pelvic area of the body. Its primary function is to collect and store the urine that has left the kidneys. Once the bladder starts to becomes full, the urine begins to leave the bladder and pass into the urethra.
The ureters are small tubes made of muscle. These structures are attached at one end to the kidneys, and to the bladder at the other. They use a small amount of pressure to gently force or push urine from the kidneys to the bladder and then from the bladder to the urethra on its way out of the body. The ureters also prevent urine from backing up and going back into the kidneys once it has passed into the bladder, a disorder which would be known as reflux.
The urethra is the final portion of the renal system. This structure is a hollow tube connected to the bladder and passes through the genitals, exiting the body. The urethra passes through the penis in males and is responsible for transporting both urine and semen. This tube is significantly shorter in females and stops just above the opening to the vagina. An external muscle known as the urethral sphincter helps to control the action of voluntary urination.
