BODY CAVITIES

Body Cavities

The cavities, or spaces, of the body contain the internal organs, or viscera. The two main cavities are called the ventral and dorsal cavities. The The ventral is the larger cavity and is subdivided into two parts (thoracic and abdominiopelvic cavtites) by the diaphragm, a dome-shaped respiratory muscle.

Abdominial and pelvic cavity

The lower part of the ventral (abdominiopelvic) cavity can be further divided into two portions: abdominal portion and pelvic portion. The abdominal cavity contains most of the gastointestinal tract as well as the kidneys and adrenal glands. The abdominal cavity is bound cranially by the diaphragm, laterally by the body wall, and caudally by the pelvic cavity. The pelvic cavity contains most of the urogenital system as well as the rectum. The pelvic cavity is bounded cranially by the abdominal cavity, dorsally by the sacruum, and laterally by the pelvis.

Thoracic cavity

The upper ventral, thoracic, or chest cavity contains the heart, lungs, trachea, esophagus, large blood vessels, and nerves. The thoracic cavity is bound laterally by the ribs (covered by costal pleura) and the diaphragm caudally (covered by diaphragmatic pleura).

Dorsal cavity

the smaller of the two main cavities is called the dorsal cavity. As its name implies, contains organs lying more posterior in the body. The dorsal caity, again, can be divided into two portions. The upper portion, or the cranial cavity, houses the brain, and the lower portion, or vertebra canal houses the spinal cord.