An overloading of the gel with a soluble protein creates a semicircular band of this protein (e. g. in the marker lane of the image at 66 KDa), allowing other proteins with similar molecular weights to be covered.
Like arrowroot, tapioca also comes from the root of a plant, however, in this case it is the root of the Cassava plant. It is ground into powdered form and is often referred to as tapioca flour.
Arrowroot or arrowroot starch is a powdery product extracted from the roots of the arrowroot plant Maranta arundinaceae. The arrowroot plant is native to South America. It is a small, perennial herb with broad, flat, ovate-shaped leaves and grows to a height of 3 to 5 feet. The root is underground and is a small, cylindrical-shaped, cream-white/light red tuber, covered with thin surface scales. They contain about 23% starch.