How can you say that mouth is a munching machine?

How can you say that mouth is a munching machine?
A. 1) the circular muscles of the mouth enable the food to be pushed into the oral cavity and to be moved around.
2) The teeth grind, chew and shred the food by a process called mastication.
3) The surface muscles of the jaw help in biting and chewing actions and moving the jaw. The jaw moves up, down, forward and backward during food mastication.
4) The teeth help in cutting and grinding , while tongue movements evenly spread out the food and help in mixing it with saliva.
5) The muscles of the mouth enable the food to be pushed in the oral cavity and to be moved around.
6) Hence we can say that mouth is a munching machine.