Kidney tubules are tiny, tube-like structures found in the kidneys. They play a crucial role in filtering blood and forming urine. Each kidney contains millions of these tubules, which are part of the nephron, the functional unit of the kidney. The tubules reabsorb essential substances like water, glucose, and salts back into the bloodstream while allowing waste products to be excreted. There are different types of kidney tubules, including the proximal convoluted tubule, loop of Henle, and distal convoluted tubule. Each type has specific functions in the reabsorption and secretion processes. Together, they help maintain the body's fluid and electrolyte balance.