Human body cavities are spaces containing interstitial fluid and organs that are associated through function. For example, within the dorsal cavity, there is the brain and spinal cord, organs necessary for transmission of nerve cell impulses throughout the body. Important for metabolism and absorption, digestive system organs are housed within the abdominal cavity, while structures responsible for reproduction are located inside of the pelvic cavity. Smaller body cavities reside in the skull that are necessary for eating, breathing, and filtering the air.
As it is the largest of the human body cavities, the ventral cavity holds the thoracic, abdominal, and pelvic organs, which are housed in three separate cavities. In anatomical terms, ventral pertains to the position of being in front, or towards the front. Even while the ventral cavity encompasses both the abdominopelvic and thoracic cavities, the abdominopelvic cavity is further divided into two cavities: abdominal and pelvic. Located in the thoracic cavity, the heart and lungs are contained in individual human body cavities such that the pleural cavities enclose each lung separately, while the heart is confined to the pericardial cavity.
Positioned in the back, the dorsal cavity is a major human body cavity as it contains the brain and spinal cord which are principle nervous system structures. More specifically, the central nervous system is composed of both the spinal cord and the brain, which is necessary for communication, interpretation, and responses to stimuli. The brain is held inside of the cranial cavity, while the spinal cord is contained within the spinal canal, a long space extending from the base of the cranium down the back. It is the vertebral foramen, a circular space found on every vertebra that forms the spinal canal as each articulates with the next vertebra in succession.
Other significantly smaller human body cavities exist, many of which reside in the skull. Housing the tongue, teeth, and gums, the oral cavity is a large opening from outside the body which leads into the digestive system where food intake and absorption occurs. Functioning much like an air filtration system, the nasal cavity is a respiratory system structure on the frontal portion of the skull covered by epithelial mucosa, the same type of tissue lining the passageways of the lungs. Four spaces of air are closely associated with the nasal cavity and are referred to as the paranasal sinuses, namely the ethmoidal, splenoid, maxilla, and the frontal sinuses. Due to allergies, in certain people, a chronic form of sinusitis develops that persists for at least several months and is characterized by postnasal drip, coughing, and stuffiness.
