Final answer:
CD8+ T cells recognize antigenic peptides presented by MHC I molecules and initiate an immune response to kill infected cells.
Step-by-step explanation:
CD8+ T cells recognize antigenic peptides presented by major histocompatibility complex (MHC) I molecules. MHC I molecules are found on the surface of nearly all cells in the body and are responsible for presenting antigens that originate from the cell's own proteins or from intracellular pathogens. When an infected cell presents an antigenic peptide on MHC I, CD8+ T cells bind to the complex and initiate an immune response to kill the infected cell.
For example, when a virus infects a cell, viral proteins are broken down into small peptides inside the cell. These peptides are transported to the cell surface where they bind to MHC I molecules. The CD8+ T cells can recognize the viral peptides presented on MHC I and destroy the infected cell.