What would happen in an ecosystem without herbivores? (2 points)
the populations of secondary consumers would decrease.
the populations of primary producers would decrease.
the populations of secondary consumers would increase.
the populations of primary consumers would increase.

trachea, alveoli, lung capillaries, arteries

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.