What is the nephron's role in the body?

The nephron is the fundamental structural and functional unit of the kidney, and its primary role is to filter blood in order to create urine. Each nephron consists of a renal corpuscle and a renal tubule. The renal corpuscle includes the glomerulus, where blood filtration occurs. Here, blood is filtered under pressure, allowing water, ions, and small molecules to pass into the tubular system while retaining larger molecules like proteins and blood cells.

Following filtration, the renal tubule modifies the filtrate by reabsorbing substances that the body needs, such as glucose and certain ions, and secreting waste products into the urine. The end product of these processes is urine, which is then collected and eventually excreted from the body. This makes the nephron crucial for maintaining fluid and electrolyte balance and for eliminating waste products from metabolism, thereby playing a vital role in homeostasis.

The other options either misrepresent the functions of the nephron or describe roles that are fulfilled by other structures in the body. For example, controlling blood pressure involves a more complex interaction of hormones and vascular structures rather than a direct function of the nephron alone, while storage of waste products typically occurs in the bladder, not in the nephron. Additionally, although