Cytochrome c from horse is widely used in biochemical research as a model protein to study electron transfer processes due to its role in the mitochondrial electron transport chain. It serves as a critical component in assays measuring cellular respiration and apoptosis, helping researchers understand mechanisms of programmed cell death. Additionally, it is employed in studies of oxidative stress and redox reactions, providing insights into cellular damage and antioxidant defense systems. Its stability and well-characterized structure make it a valuable tool in enzymology and structural biology research.