What type of organisms are all members of the subphylum Urochordata?

Tunicates...also known as sea squirts

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex

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.