Ask questions using the parenthesized words: 1 the alimentary canal is a muscular tube about 9 maters long. (what size) 2 the wall of the alimentary canal consists of four disfinct layers. (how many) 3 mucous membrane is formed of surface epithelium and a small amount of smooth muscle. (what of) 4 the mucosa protects the tissues beneath. (what) 5 the fibers of the outer muscular coat run lengthwise. (how) 6 the cells of the serosa secrete serous fluid. (what)