Food enters the body through the mouth where it is mixed with digestive enzymes from the these enzymes begin the digestion of into the bolus is propelled to the pharynx by the tongue. the closes over the upon swallowing to protect the respiratory tract from food particles.

Food enters the body through the mouth where it is mixed with digestive enzymes from the  saliva. These enzymes begin the digestion of starch into sugars. The bolus is propelled to the pharynx by the tongue. The epiglottis closes over the   tracheid upon swallowing to protect the respiratory tract from food particles

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: