The kidneys of vertebrates and humans are plentifully supplied with blood, from which urine is formed by filtration and reverse selective absorption. This process occurs in nephrons located in the kidneys. Each nephron consists of a capsule and a system of convoluted tubules. Inside the capsule is a capillary glomerulus formed by blood vessels.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.