Phagocytosis and the inflammatory response. Macrophages are a cornerstone of the innate immune system. ... Recent work indicates that Toll-like receptors play a key role in reading a "bar code" on invading microorganisms and in eliciting a specific immune respone.
The reproductive system is different from other body systems in that the reproductive system functions in the survival of a species while all other body systems function to ensure the survival of the individual.
because what they produce, it for animals to eat and because they are at the bottom of the ecosystem food chart. and also oxygen
Producers, herbivores, secondary consumers, apex predators
