Final answer:
The nephron is the functional and structural unit of the kidneys, consisting of the renal corpuscle, renal tubule, and capillary network, and is responsible for urine production.
Step-by-step explanation:
The functional and structural unit of the kidneys is the nephron. Each kidney contains over one million nephrons, which are responsible for filtering blood and forming urine. A nephron includes three main components: the renal corpuscle, the renal tubule, and the associated capillary network. These structures work together to remove waste products from the blood, such as urea and uric acid, and to produce urine through the complex processes of filtration, absorption, and secretion.