feedback is when the body reacts in the same direction as a stimulus. Negative
Positive

It's Positive.

Negative is when it reacts against the direction as a stimulus  

format change of dna.  

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.