<span>A nephron is the basic structural and
functional unit of the kidney. Its functions are to regulate the
concentration of water and soluble substances like sodium salts by
filtering the blood, reabsorbing what is needed and excreting the rest
as urine. A nephron eliminates wastes from the body, regulates blood
volume and blood pressure, controls levels of electrolytes and
metabolites, and regulates blood pH. Its functions are vital to life and
are regulated by the endocrine system by hormones such as antidiuretic
hormone, aldosterone, and parathyroid hormone. In humans, a normal
kidney contains 800,000 to 1.5 million nephrons, we have so many because
we need them
