PHS 7.1 – Basic Structure of the Human Body Practice Test 2025 - Free Practice Questions and Study Guide

The urinary system is primarily responsible for removing waste products from the body. It performs this function by filtering blood through the kidneys, where waste products, excess water, and other substances are removed to form urine. This urine is then stored in the bladder until it is excreted from the body through the urethra.

In contrast, the other systems listed serve different primary functions. The respiratory system helps in the exchange of gases, primarily oxygen and carbon dioxide, which is crucial for maintaining the body’s oxygen levels and removing carbon dioxide. The digestive system breaks down food into nutrients that the body can absorb; while it does eliminate waste, its main role is nutrient absorption. The endocrine system regulates hormones that control a variety of bodily functions, such as metabolism, growth, and mood. Thus, the urinary system is specifically designed for the removal of metabolic wastes and the regulation of body fluids.