Able to move and attack quickly, neutrophils are blood cells that serve as a quick response team at the first sign of infection.  They can eat bacteria and other pathogens whole.  They cause inflammation which sends an alarm for more immune cells to come to the attack.

  

Description:  a.k.a. - "Seg", PMN.  A white blood cell and the main component of pus.

Location:  Neutrophils patrol the bloodstream and, like a good watchdog, are attracted by the scent of invading bacteria.  Once the enemy is detected, the neutrophils quickly travel through the tissues to attack the microscopic invaders.  Neutrophils give their lives to protect you - once they have left the bloodstream and eaten thier share of bacteria, the neutrophils will die.

Weapons:  

• Internal granules - contain chemicals designed to help digest eaten bacteria. 
• Chemical "grenades" - induce inflammation, blows holes in bacteria, and destroys damaged tissue.

Life span:  Usually less than a few days once released from the bone marrow.

Number: As many as 1 trillion are produced daily in an average adult, around 40 billion of these can be found traveling throughout the body by way of the bloodstream, however this number can rise quickly to fight infection.

Appearance:  12-14 micrometers in height, contains a single large nucleus with multiple lobes that looks like a piece of popcorn.

Source: Arise from stem cells in the bone marrow.