What is the function of proton pumps localized in the plant plasma membrane?

proton pump creates the electrochemical gradients in the plasma membrane of plants, fungi, protists, and many prokaryotes also they push hydrogen ions from areas of low concentration to areas with high concentration

that is wrong, its not thymus.

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.