Describe the main differences between the innate and adaptive immune response?

The innate immune response is broader and faster than the adaptive. It is able to react against a wide variety of different pathogens including viruses, bacteria and parasites. It is non-specific, meaning it gives a repeated general response that does not vary between different pathogens. It does not lead to the formation of immunological memory. In contrast the adaptive immune system develops memory which acts as protection to future infections.  This means that with repeated exposure to the same antigen on a pathogen the immune response becomes faster and eliminates the pathogen more efficiently. The innate system serves to protect the body against infections for example influenza virus. However the adaptive system is also able to orchestrate complex immune responses (e.g. anti-cancer CD8 positive killer T cells) and discriminate between self and non-self. It does this by the recognition of cell surface molecules called major histocompatibilty class antigens that present small protein fragments or peptides. The adaptive system can be divided into humoral immunity (B cells) and cellular immunity (T cells). This is different to the innate system which involves physical barriers such as skin and mucous, the process of inflammation and cells such as macrophages which are phagocytes that engulf foreign material.