Immunometabolism is the crosstalk between metabolic and immunological processes. Mitochondria, the cellular structures that generate cell energy, are key elements in the crosstalk between metabolic and immune signaling pathways. 

The adaptive immune system is responsible for the more complex and optimized immune responses that develop when innate immunity is insufficient to manage a threat. It is the specific immunity we acquire over time as the immune system is challenged with new antigens and learns to deal with them.