What is the primary function of the urinary bladder?

The urinary bladder primarily serves the function of storing urine before it is expelled from the body. It acts as a reservoir that collects urine produced by the kidneys through the process of filtration and reabsorption. As urine accumulates in the bladder, it stretches to accommodate the increasing volume, enabling the body to manage its waste more efficiently.

Once the bladder reaches a certain capacity, it signals the brain, indicating the need to void. This allows for voluntary control over urination, helping to maintain proper fluid balance and waste elimination in a manner that is adaptive to various physiological needs.

The other functions listed do not pertain to the bladder itself. While the kidneys are responsible for the production and filtration of urine, the bladder's role is solely to store it. Blood pressure regulation is controlled by various systems in the body, including the kidneys and cardiovascular system, but not specifically by the urinary bladder.