We can describe the abdomen and pelvis by dividing them into cavities, or based on the way they are divided into quadrants or regions.
Cavities
The abdominopelvic cavity is split into the larger abdominal cavity and the smaller pelvic cavity.
Abdominal cavity
- Extends between the thoracic diaphragm superiorly and the pelvic cavity inferiorly (they are continuous, therefore this border is only arbitrary and no physical)
- Houses the majority of the GIT, spleen, and kidneys
Pelvic cavity
- Extends between the abdominal cavity superiorly (once again — they are continuous), and the pelvic diaphragm (discussed in the Perineum lesson)
- Houses part of the GIT and the urogenital system (excluding the kidneys)

Divisions
We can divide the abdomen and