In the mouth grinding of food is brought about by __1__ and __2__ . The saliva contains __3__ enzymes. The food then passes to stomach through pharynx and __4__. Peristalsis of food is caused by __5__. In the stomach pepsin acts on proteins to change them into __6__ and __7__. Bile is secreted by __8__. In duodenum, pancreatic juice has __9__ and __10__ enzymes. Lipase acts on fats and converts them into __11__ and __12__ .