Whenever you catch a cold, cut a finger or skin a knee, your immune system gets to work. But how does this system actually work? And what organs are involved? This video will teach us about the human immune system and how it keeps us healthy. We?ll be going through concepts like transmission, allergies, and blood cells. We?ll also be taking a look at the difference between the immune system as a whole and our body?s defenses. To wrap things up, we?ll describe a few immune system disorders and also provide a few pointers to promote a healthy immune system.