What is the primary purpose of the urinary system?

• A. To absorb nutrients from food
• B. To remove waste products from the blood and maintain electrolyte balance
• C. To facilitate gas exchange in the lungs
• D. To produce hormones for metabolism regulation

Answer: (B)

The primary purpose of the urinary system is to remove waste products from the blood and maintain electrolyte balance. This system plays a crucial role in filtering the blood to eliminate harmful substances, such as urea and creatinine, which are products of protein metabolism. By doing so, it ensures that the body's internal environment remains stable, a condition known as homeostasis.

Additionally, the urinary system regulates water balance and various electrolytes (such as sodium, potassium, and calcium) within the body. This is essential for numerous physiological processes, including muscle function and nerve transmission. The kidneys, which are the core organs of the urinary system, perform this filtration and regulation.

The other options focus on different body systems that do not directly relate to the primary functions of the urinary system. The absorption of nutrients pertains to the digestive system, gas exchange is associated with the respiratory system, and hormone production for metabolism regulation is primarily conducted by the endocrine system. Thus, the urinary system is specifically designed for waste removal and electrolyte management, highlighting the importance of option B.