When you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. This increases the space in your chest cavity, into which your lungs expand. The intercostal muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale<span />
Answer:
to cross the plasma membrane.
Explanation:
Two classes of proteins that mediate facilitated diffusion are generally distinguished: carrier proteins and channel proteins.
I guess machinery used to cut down trees can use fossil fuels, they also transform co2 into sugar, cellulose and other carbon-containing carbohydrates.
