What is the final product collected by the kidneys as waste?

The final product collected by the kidneys as waste is urine. This is the result of the kidneys' filtration process, where they remove waste products and excess substances from the blood. As blood passes through the kidneys, they filter out toxins, urea, and other metabolites, which are combined with water to form urine. Once urine is produced, it is stored in the bladder until it is expelled from the body. This process is essential for maintaining the body's fluid balance and removing harmful substances, thus highlighting the crucial role of the kidneys in the body's excretory system.