The trachea connects the larynx and bronchi. It is lined with a mucus membrane with respiratory epithelium and a lamina propria, and a submucosa containing horseshoe shape hyaline cartilages and numerous mucus and mixed glands (Trachea 1).
Arrowroot starch and tapioca flour are two products that are used quite a bit in gluten-free cooking and baking. They are used to replace corn starch and wheat flour in various recipes. Arrowroot starch can sometimes substitute for tapioca flour depending on the application.
Arrowroot, or arrowroot starch, is a powdery product made from the arrowroot plant, a starchy tropical root. The plant is dried and ground up to make the powder, which is primarily used as a thickener in the kitchen, much like cornstarch. Much like cornstarch, it is an excellent thickening agent. It has about twice the thickening power of regular flour. Unlike cornstarch, however, arrowroot is completely flavorless and will not impart a starchy taste into puddings or other dishes that it is used to thicken. Another reason that arrowroot is called for in recipes is that it is extremely digestible, moreso than regular wheat flour.