BIO 1101: Introduction to Anatomy and Physiology - Body Cavities, Fluids, and Homeostasis

This set of vocabulary flashcards covers introductory anatomy and physiology concepts including body cavities (dorsal and ventral), body fluid compartments, and the mechanisms of homeostasis (negative and positive feedback).

Body Cavities

Hollow spaces that house and protect organs.

Dorsal (posterior) Body Cavity

The body cavity that includes the cranial and vertebral cavities.

Cranial Cavity

The space inside the bony skull that contains the brain.

Vertebral (Spinal) Cavity

The cavity that extends from the cranial cavity to nearly the end of the vertebral column and contains the spinal cord.

Ventral (anterior) Body Cavity

The body cavity subdivided into the thoracic and abdominopelvic cavities.

Thoracic Cavity

The superior portion of the ventral body cavity containing the pleural cavities, mediastinum, and pericardial cavity.

Pleural cavities

Two lateral cavities within the thoracic cavity that each contain a lung.

Mediastinum

The central region of the thoracic cavity containing the aorta, esophagus, and the heart (within the pericardial cavity).

Pericardial cavity

The specific space within the mediastinum that houses the heart.

Abdominopelvic Cavity

The inferior portion of the ventral body cavity subdivided into the abdominal and pelvic cavities.

Abdominal Cavity

The cavity containing the stomach, liver, and intestines.

Pelvic Cavity

The cavity containing reproductive organs, urinary organs (except kidneys), and the terminal digestive tracts.

Intracellular Fluid

The fluid found within the cells; a component of the $70\%$ of the body composed of water.

Extracellular Fluid

Fluid found outside the cells.

Interstitial Fluid

Fluid located in the spaces between cells.

Blood plasma

The fluid found within blood vessels.

Homeostasis

The maintenance of a stable, constant internal environment within an organism.

Negative Feedback

A control mechanism where a change in a variable triggers responses that move the variable in the direction opposite to the original change to facilitate homeostasis.

Receptor

The component of a feedback mechanism that detects a stimulus, such as a thermometer detecting heat.

Control center

The component of a feedback mechanism that processes information and maintains a set point, such as the hypothalamus set to $98.6\text{ degrees}$.

Effector

The component of a feedback mechanism that carries out the response, such as cooling mechanisms like sweating or an air conditioner.

Insulin

A hormone released by the pancreas when blood glucose levels rise, causing cells to take up glucose and lowering blood glucose levels via negative feedback.

Positive Feedback

A less common system that leads to the acceleration of a process in the same direction as the original stimulus.

Oxytocin

A hormone released during labor due to uterine wall and cervix stretch, which causes contractions and further release of the hormone in a positive feedback loop.