Anatomical Directions, Planes & Cavities (Part 2)

The frontal plane separates the anterior (front) and posterior (rear) portions of a body or organ. It is also known as the coronal plane. ("Corona" means crown in Latin.)

In transverse planes, bodies and organs are divided horizontally into upper and lower parts. Cross-section images are the result of transverse planes.

In the anatomical position, the body is positioned with its feet together, arms to the side, and head, eyes, and palms forward.

Directional terms describe the arrangement of structures in relation to each other or to other body parts.

A body plane is a geometric plane that divides the body into sections. In both human and zoological anatomy, they are commonly used to describe the location or direction of bodily structures.

Median planes are also called mid-sagittal planes, because they cross vertically through the navel to form the sagittal plane, which divides the body exactly into left and right sides.

In the body, a cavity is any space, compartment, or potential space. Cavities accommodate organs and other structures; cavity as potential space can contain fluid.

The dorsal cavity is located along the posterior surface of the body and consists of two different cavities. The brain resides in the cranial cavity, whereas the spinal cord resides in the vertebral cavity. Meninges form the protective covering for the dorsal cavity.

The ventral body cavity is located in the anterior part of the body. It is composed of the thoracic cavity and the abdominopelvic cavity.

Cranial cavity, also called intracranial space, refers to the space in the skull. A space inside the skull is made up of eight cranial bones called the neurocranium.

Within the vertebral column, the spinal canal (or vertebral canal or spinal cavity) contains the spinal cord. Vertebrae form the spinal canal, which is the path the spinal cord takes.

The upper ventral or thoracic cavity houses the heart, lungs, trachea, esophagus, major blood vessels, and nerves. Laterally, the thoracic cavity is bounded by the ribs (covered by the costal pleura) and caudally by the diaphragm (covered by the diaphragmatic pleura).

The abdominal cavity and pelvic cavity are part of the abdominopelvic cavity. The stomach, liver, pancreas, gallbladder, spleen, kidneys, and small and large intestines are located here. The bladder and reproductive organs are also found here.