What is the basic function of the urinary system?

The primary function of the urinary system is to remove waste products from the blood. This system includes the kidneys, ureters, bladder, and urethra, working together to filter the blood, excreting waste in the form of urine. The kidneys play a vital role in this process by filtering out toxins, excess salts, and urea, which is a byproduct of protein metabolism. By effectively eliminating these waste products, the urinary system helps maintain the body’s internal balance of electrolytes and fluids. This function is critical for overall homeostasis, ensuring that harmful substances do not accumulate in the bloodstream, which could lead to serious health issues.

The other options pertain to different physiological systems: nutrient absorption is a role of the digestive system, oxygen transport is managed by the circulatory system with the help of the respiratory system, and temperature regulation is primarily executed by the integumentary system, involving the skin and sweat glands. Thus, while each option refers to an essential bodily function, only the one about waste removal accurately describes the fundamental role of the urinary system.