When you breathe in, or inhale, your diaphragm contracts and moves downward. This increases the space in your chest cavity, and your lungs expand into it. The muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale
Lipids have the same elements as carbohydrates, but differ in their linkage. While the exact chemical structure of lipids varies, they generally have a much greater ratio of hydrogen-to-oxygen than carbohydrates.
