Ex vivo models are experimental systems that allow researchers to study biological processes or diseases outside of the living organism they originate from. These models typically involve removing tissues or cells from an organism and keeping them alive in a controlled environment for study. Ex vivo models are commonly used in fields such as pharmacology, toxicology, and regenerative medicine to investigate the effects of drugs, toxins, or therapies on specific tissues or cells. These models can provide valuable insights into biological mechanisms and disease processes, helping researchers to develop and test new treatments.