Defense Barrier

                                                                        Post 4

                          

                                                                Defense Barrier

The first line of defense (or outside defense system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, ‘friendly’ bacteria and white blood cells called neutrophils.

Pathogenic (disease-causing) microorganisms must make it past this first line of defense. If this defense is broken, the second line of defense within your body is activated.