Which cavity is divided into upper abdominal and lower pelvic portions?

• A. Abdominopelvic Cavity
• B. Abdominal Cavity
• C. Thoracic Cavity
• D. Pelvic Cavity

Answer: (A)

The abdominopelvic cavity is the continuous space that spans from just below the diaphragm down to the pelvic inlet, and it's commonly treated as two regions: an upper abdominal part and a lower pelvic part. The diaphragm marks the boundary with the thoracic cavity, while the pelvic brim/inlet marks the division between the abdominal and pelvic portions. This setup explains why digestive organs sit in the abdominal region while urinary and reproductive organs reside in the pelvic region. The abdominal cavity alone or the pelvic cavity alone don’t cover both regions, and the thoracic cavity is a separate space above the diaphragm.