Proteins are structures that carry out specific essential functions of life through systems of specialized cells. Explain this.

b brown mice / white sand dunes

thinking it would be d not too sure but i think it's right

      n

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 enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.