The Immune System

The immune system is processes within an organism or a system of biological structures and that protects against disease. To make function proper an immune system must detect a broad variety of agents from viruses to parasitic worms and differentiate them from the organism's own healthy tissue.Pathogens can rapidly involve and adapt to avoid neutralization and detection through the immune system. By result, multiple defense mechanisms have also evolved to neutralize and recognize pathogens.

Even simple unicellular organisms like as bacteria possess a rudimentary immune system, in the structure of enzymes which protect against bacteriophage infections. Another basic immune mechanism evolved in ancient eukaryotes and remains in their modern descendants, like as insects and plants. These mechanisms involve phagocytosis, antimicrobial peptides known defensins and the complement system. Jawed vertebrates, involving humans, have even more sophisticated defense mechanisms, involving the ability to adapt over time to recognize