Download Introduction to the Urinary System

Introduction to the Urinary System
Major Functions of the Urinary System
Usually, when we think of the urinary system, we think about getting rid of waste
products in our urine. The urinary system, however, involves more than just
waste removal. The urinary system plays many important roles in the
maintenance of homeostasis. This means this system helps to regulate the
internal conditions of the whole body. For instance, if the body is dehydrated, the
body will function to conserve the liquid. Consequently, the body does not
produce large volumes of urine. Much of this proper maintenance of homeostasis
is a function of the kidneys.
The roles of the urinary system include detoxifying harmful substances (or
toxins), maintaining water levels, maintaining appropriate levels of some
vitamins and minerals, maintaining acid-base and electrolyte balances, and
interacting with the circulatory system to help regulate blood pressure and red
blood cell count. In a three-way interaction with both the respiratory and the
circulatory systems, the urinary system helps stabilize blood oxygen and carbon
dioxide levels.
The final outcome of the above functions of the urinary system is excretion.
Excretion is the removal of wastes generated by the normal processes of cell
metabolism in the body. Such metabolic wastes include urea, uric acid,
creatinine, creatine, bilirubin, and ammonia. The metabolic wastes originate in
the cells throughout the body and are moved into the blood. If allowed to
accumulate, these wastes would be toxic to the body. All of the organs of the
urinary system are involved in the removal of these metabolic wastes by
contributing to the process of excretion. Other body systems that are also
involved in excretion are the respiratory system, integumentary system (the
skin), and the digestive system. Excretion and elimination are two similar
processes. Excretion specifically referes to the removal of the waste products of
metabolism from the body. Elimination is the explulsion of undigested or
unmetabolized waste products from the body.
Let's Summarize
The major functions of the urinary system include:
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Excretion of waste products such as urea, uric acid, creatinine, bilirubin,
and ammonia.
Maintenance of homeostasis, or the ability for the urinary system to
regulate its internal conditions.
Detoxifying harmful substances in the body
Maintenance of proper water levels, vitamin and mineral levels, and
acid-base and electrolyte levels
Interaction with the respiratory and the circulatory systems, to help
stabilize blood oxygen and carbon dioxide levels.