Answer by 1Jazz. Confidence votes 9.4K. The Peritoneum is the serous membrane that lines the abdominal cavity. The parietal peritoneum lines the abdominal wall, and the visceral peritoneum lines the outside of the organs within the cavity.The viseral and parietal peritoneum line the abdominal cavity. Peritoneum.parietal peritoneum. peritoneum.peritoneum.nswer by 1Jazz. Confidence votes 9.4K. The Peritoneum is the serous membrane that lines the abdominal cavity. The parietal peritoneum lines the abdominal wall, and the visceral peritoneum lines the outside of the organs within the cavity.