Which of the following does the urinary system not do?

The urinary system plays a vital role in various bodily functions, including reabsorbing water, regulating blood pressure, and maintaining acid-base balance. However, it does not excrete excess albumin molecules. Albumin is a protein that is typically retained in the bloodstream due to its size and function. When the kidneys are functioning properly, they reabsorb albumin that may enter the filtrate back into the bloodstream. The presence of excess albumin in urine can indicate damage to the kidneys, as they fail to filter or retain this protein correctly, a condition known as proteinuria.

In contrast, reabsorbing water is a crucial function of the kidneys, especially in maintaining hydration levels and regulating blood volume. The kidneys also play an essential role in regulating blood pressure through mechanisms such as the renin-angiotensin-aldosterone system. Additionally, the urinary system helps maintain the acid-base balance by regulating the excretion of hydrogen ions and bicarbonate, thus aiding in the overall homeostasis of pH in the body.