If you poke and prod at your abdomen, you might be tempted to think that your body is a solid mass of bone, muscle, organs, and tragically for some of us, fat. But it turns out that bodies actually contain many important spaces or cavities. Some of these cavities, like for example the nasal cavity, open to the outside of the body. However, most of the Most of our cavities are internal. Body cavities have several important functions.
Firstly, they protect delicate organs, like for example the brain, from bumps and shock when we walk, run and jump. Secondly, cavities allow internal organs to change shape and size. For example, our lungs, stomach and bladder can all expand and contract because they sit inside cavities.
And lastly, body cavities provide a warm, nurturing space for foreign creatures to implant into, grow and burst from in the alien movies. That's it man! Game over man, game over!
The human body consists of two main cavities. The dorsal body cavity and the ventral body cavity. If you're not sure what the terms dorsal and ventral mean, check out my other video on anatomical terminology. Let's start with the dorsal body cavity. It can be divided into two parts, the cranial cavity and the spinal cavity.
The cranial cavity is the space formed by the bones of the spine. skull. It contains the brain.
The spinal cavity, which is sometimes also called the vertebral canal, is a space formed by the bones of the vertebral column. The spinal cavity contains the spinal cord. Next is the ventral body cavity. It can be subdivided into two parts, the superior thoracic cavity and the inferior abdominal pelvic cavity, which are separated by a flat muscular sheet called the diaphragm. The thoracic cavity can be subdivided into the left and right pleural cavities and a central pericardial cavity.
The pleural cavities contain the lungs and the pericardial cavity contains the heart. Separating these three cavities is a partition called the mediastinum. The abdominopelvic cavity can be subdivided into a superior abdominal cavity and an inferior pelvic cavity.
The abdominal cavity contains the stomach, liver, spleen, kidneys, small intestine and most of the large intestine. The pelvic cavity contains the bladder and internal reproductive organs. Thanks for watching.
Subscribe to my channel and stay tuned for more Human Biology Explained videos.