The immune system is a system of many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue.o function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue.
The cost to run for president in the general election can amount to at least $70 million USD, although the amount of money required can vary. It is possible that at some point in the future, all presidential candidates will run without taking any federal contributions.
President Obamaâs reelection campaign spent $683 million, and the Democratic Party and outside groups pushed the total to $1.1 billion, according to FEC filings.Then-Sen. Barack Obama (D-Ill.) spent $730 million on the presidential election; while Sen. John McCain (R-Ariz.) spent $333 million.resident Obamaâs reelection campaign spent $683 million, and the Democratic Party and outside groups pushed the total to $1.1 billion, according to FEC filings.