Final answer:
Urine formation involves glomerular filtration, tubular reabsorption, and tubular secretion.
Step-by-step explanation:
The process of urine formation involves three main steps: glomerular filtration, tubular reabsorption, and tubular secretion.
- Glomerular filtration occurs in the glomerulus of the nephron. It involves the filtration of blood plasma through the glomerular capillaries to form a filtrate that contains water, ions, and small molecules.
- Tubular reabsorption takes place in the renal tubules. It involves the selective reabsorption of water, glucose, amino acids, and other essential molecules from the filtrate back into the bloodstream.
- Tubular secretion also occurs in the renal tubules. It involves the active transport of waste products, excess ions, and drugs from the bloodstream into the filtrate, further modifying its composition.