So, let's begin by discussing our innate Immunity and the different components that make up our innate Immunity. And let's begin with the physical barrier our skin. So, our skin is the largest organ of our body, and one of the more important functions of our skin is to actually physically protect our body from different types of pathogens for example, UV radiation, as well as bacterial cells and viruses. So, our skin creates a physical barrier that prevents pathogens from entering our body and attacking our cells. Now, if we examine the passageways inside our body, the air passageways, including the nasal cavity, the trachea, the bronchi, as well as the bronchioles found in the lungs, these air passageways are lined with a special type of mucus membrane. And this sticky and sliding mucus membrane is responsible for trapping the pathogens that enter our body through the process of breathing.