2. Some cells are covered in cilia, which are tiny hair-like structures. What are two functions of cilia?
A. grooming and expelling waste
B. movement and grooming
c. movement and obtaining food
D. obtaining food and expelling waste

b. heterotroph

explanation:

the answer to your question is tooth decay.

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.