Final answer:
Natural killer (NK) cells participate in both nonspecific resistance and the immune response by destroying virally infected cells and also collaborating with cytotoxic T cells.
Step-by-step explanation:
The cell that participates in both nonspecific resistance and the immune response is the Natural killer (NK) cell. NK cells play a key role in the innate immune system by recognizing and destroying cells that do not express "self" proteins on their plasma membrane or that contain foreign or abnormal markers, such as virus-infected cells or cancer cells. They also share a cell-killing mechanism with cytotoxic T cells (Tc) of the adaptive immune response, which allows them to work in concert with cytotoxic T cells against virally infected cells. This collaboration is critical for the body's defense as it allows these immune cells to attack and kill virally infected cells before the virus can complete its replication cycle, thereby stopping the production of infectious particles and aiding in the prevention of disease spread.