Now, let's focus on something called lung volume and lung capacity. So in this lecture we're going to explore questions such as how much air is typically exchanged by our lungs every single time we take a break breath, and how much air can actually be stored inside our lungs in the first place. So let's begin by taking a look at the following diagram. The Y axis is the volume of air that is exchanged by the lungs given to us in milliliters. And the x axis is our time. Now notice as time increases, as time progresses, we have this fluctuating blue curve.