On most bicycles, the tires include a separate inner tube inside the tire itself. when the inner tube is inflated, often to pressure greater than 100 pounds per square inch, it does not burst because the walls of the tire support it. without the tire, the inner tube would burst long before such high pressures were reached. similarly, the cytoplasm of plant cells in hypotonic conditions is under relatively high osmotic pressure. however, the cells do not lyse (or burst) due to the presence of the _ that provides structural support for the _.