What organs are primarily included in the urinary system?

The urinary system is responsible for the production, storage, and elimination of urine, which is a liquid waste product filtered from the blood. The primary organs involved in this system are the kidneys, ureters, urinary bladder, and urethra.

The kidneys play a crucial role in filtering blood to create urine, regulating electrolytes, and maintaining fluid balance in the body. The urine produced in the kidneys passes through the ureters, which are tubes that connect each kidney to the urinary bladder. The bladder serves as a reservoir for urine until it is ready to be expelled from the body through the urethra.

Understanding this structure is essential, as it highlights the coordinated functions of these organs in waste elimination and homeostasis. Other options listed represent organs from different body systems; for instance, the heart, lungs, and blood vessels are part of the cardiovascular system, while the liver, pancreas, and gallbladder are associated with the digestive system. The stomach, intestines, and rectum are also part of the digestive tract, not involved in the urinary processes. Thus, the correct answer underscores the specific organs that collectively function as the urinary system.