9. The dorsal body cavity protects nervous system organs and contains the cranial cavity subdivision to encase the brain and the vertebral or spinal cavity subdivision to enclose the spinal cord. The ventral body cavity has two major subdivision of the thoracic cavity and the abdominopelvic cavity. The ventral body cavity houses internal organs. Major organs contained in them are ribs and chest muscles, the lungs, heart, esophagus, trachea, and various others.
10. The walls of the ventral body cavity and the outer surfaces of the organs are covered by a thin double layered membrane called the serous membrane. The part lining the cavity walls is called the parietal serosa. It folds on itself to form the visceral serosa and the thin layer of lubricating fluid is called the serous fluid which allows organs to slide without creating friction along the cavity walls.