Question

multiple choice question

the ______ separates the thoracic cavity from the abdominal cavity.

• internal oblique
• diaphragm
• pleural lining
• rectus abdominis

Explanation:

Identify the anatomical boundary

Using the Diaphragm Function and Thoracic Cavity Subdivisions knowledge points

• The thoracic cavity (containing the heart and lungs) is located superiorly to the abdominal cavity (containing digestive organs).
• The dome-shaped skeletal muscle that physically partitions these two major subdivisions of the ventral body cavity is the diaphragm.

Evaluate the other options

• internal oblique: An abdominal wall muscle involved in rotating and flexing the trunk.
• pleural lining: The serous membrane surrounding the lungs within the thoracic cavity.
• rectus abdominis: A superficial abdominal muscle ("abs") that flexes the vertebral column.

Answer:

• internal oblique
• diaphragm (Correct answer)
• pleural lining
• rectus abdominis