Elijah goes to sleep while his intestines digest his supper. His intestine is a type of _. A. voluntary muscle
B. involuntary muscle
C. cardiac muscle

it would lead to upper respiratory infections and pneumonia.

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.