Ch.2- Body Cavities

Parietal Layer

The outer layer that lines the cavities (i.e., parietal pleura and parietal peritoneum).

Mediastinum

-A central region between the two lungs. -Contains the heart, aorta, esophagus, trachea, and thymus gland.

Pleura

Is subdivided, forming the pleural cavity and the pericardial cavity.

Viscera

A group of internal organs within the ventral cavities.

Cavity

Open space in the body.

Pleura/ Peritoneum

-All cavities are lined by, and viscera are encased in, a two-layer membrane called: -the pleura in the thoracic cavity -the peritoneum in the abdominopelvic cavity

Diaphragm

-An actual physical wall between the thoracic cavity and abdominopelvic cavity. -A muscle used for breathing.

Kidneys

-Are the only major abdominopelvic organ located outside the sac formed by the peritoneum. Because they are found behind this sac, their position is referred to as retroperitoneal (pertaining to behind the peritoneum). -Not in any body cavity.

Thoracic Cavity

-Contains the two lungs, the heart, and the mediastinum. -Includes the pleural, pericardial, and mediastinum cavities.

Pelvic Cavity

-Contains the urinary bladder, ureters, urethra, and portions of the small intestines and colon. -Female: uterus, ovaries, fallopian tubes, vagina -Male: prostrate gland, seminal vesicles, portion of the vas deferens

Ventral Cavities

-Includes the thoracic and abdominopelvic cavity. -Organs within this cavity are referred to as viscera.

The body

-Is not a solid structure, has many many open spaces or cavities. -The body can be divided into four major cavities: 2 dorsal cavities, and 2 ventral cavities.

Abdominopelvic Cavity

-Subdivided into a superior (above) abdominal cavity and an inferior (below) pelvic cavity. -The organs of the digestive, excretory (eliminates wastes), and reproductive systems are located in these cavities. -Is subdivided into regions so different areas can be precisely referred to. Two different methods of subdividing are: -the anatomical divisions (tic-tac-toe) -the clinical divisions (four boxes)

Abdominal Cavity

Contains stomach, spleen, liver, gallbladder, pancreas, and portions of the small intestines and colon.

Cranial Cavity

Contains the brain

Pericardial Cavity

Contains the heart

Pleural Cavity

Contains the lungs

Spinal Cavity

Contains the spinal cord

Dorsal Cavities

Includes the cranial and spinal cavity.

Visceral Layer

The inner layer that encases the viscera (i.e., visceral pleura and visceral peritoneum).