Which cavity is separated from the thoracic cavity by the diaphragm?

Which cavity is separated from the thoracic cavity by the diaphragm?

• A. Abdominopelvic Cavity
• B. Pleural Cavities
• C. Pericardial Cavity
• D. Thoracic Cavity

Answer: (A)

The diaphragm acts as a physical boundary that separates the thoracic cavity, which houses the lungs and heart, from the abdominal and pelvic regions. Because the diaphragm forms the bottom wall of the thoracic cavity and the top boundary of the abdominopelvic cavity, it creates a division between these two spaces. The pleural and pericardial cavities are inside the thoracic cavity, so they aren’t separated from it by the diaphragm. The thoracic cavity itself sits above the diaphragm, so it isn’t separated from anything by that muscle. Therefore, the cavity separated from the thoracic cavity by the diaphragm is the abdominopelvic cavity.

The diaphragm acts as a physical boundary that separates the thoracic cavity, which houses the lungs and heart, from the abdominal and pelvic regions. Because the diaphragm forms the bottom wall of the thoracic cavity and the top boundary of the abdominopelvic cavity, it creates a division between these two spaces. The pleural and pericardial cavities are inside the thoracic cavity, so they aren’t separated from it by the diaphragm. The thoracic cavity itself sits above the diaphragm, so it isn’t separated from anything by that muscle. Therefore, the cavity separated from the thoracic cavity by the diaphragm is the abdominopelvic cavity.