Which directional term means near the surface

Also as with a compass rose, each directional term often has a counterpart with converse or opposite meaning. These terms are very useful when describing the locations of structures to be studied in dissections. Anatomical directional terms can also be applied to the planes of the body. Body planes are used to describe specific sections or regions of the body. Below are examples of some commonly used anatomical directional terms and planes of the body.

Anterior: In front of, front Posterior: After, behind, following, toward the rear Distal: Away from, farther from the origin Proximal: Near, closer to the origin Dorsal: Near the upper surface, toward the back Ventral: Toward the bottom, toward the belly Superior: Above, over Inferior: Below, under Lateral: Toward the side, away from the mid-line Medial: Toward the mid-line, middle, away from the side Rostral: Toward the front Caudal: Toward the back, toward the tail Bilateral: Involving both sides of the body Unilateral: Involving one side of the body Ipsilateral: On the same side of the body Contralateral: On opposite sides of the body Parietal: Relating to a body cavity wall Visceral: Relating to organs within body cavities Axial: Around a central axis Intermediate: Between two structures.

Imagine a person standing in an upright position. Now imagine dissecting this person with imaginary vertical and horizontal planes. This is the best way to describe anatomical planes. Anatomical planes can be used to describe any body part or an entire body. View a detailed body plane image. Lateral Plane or Sagittal Plane: Imagine a vertical plane that runs through your body from front to back or back to front.

This plane divides the body into right and left regions. Frontal Plane or Coronal Plane: Imagine a vertical plane that runs through the center of your body from side to side. This plane divides the body into front anterior and back posterior regions.

Transverse Plane: Imagine a horizontal plane that runs through the midsection of your body. This plane divides the body into upper superior and lower inferior regions. Some anatomical structures contain anatomical terms in their names that help identify their position in relation to other body structures or divisions within the same structure.

Some examples include the anterior and posterior pituitary , superior and inferior venae cavae , the median cerebral artery, and the axial skeleton. Affixes word parts that are attached to base words are also useful in describing the position of anatomical structures. These prefixes and suffixes give us hints about the locations of body structures. For example, the prefix para- means near or within.

The anterior ventral cavity has two main subdivisions: the thoracic cavity and the abdominopelvic cavity see Figure 1. The thoracic cavity is the more superior subdivision of the anterior cavity, and it is enclosed by the rib cage.

The thoracic cavity contains the lungs and the heart, which is located in the mediastinum. The diaphragm forms the floor of the thoracic cavity and separates it from the more inferior abdominopelvic cavity.

The abdominopelvic cavity is the largest cavity in the body. Although no membrane physically divides the abdominopelvic cavity, it can be useful to distinguish between the abdominal cavity, the division that houses the digestive organs, and the pelvic cavity, the division that houses the organs of reproduction. The more detailed regional approach subdivides the cavity with one horizontal line immediately inferior to the ribs and one immediately superior to the pelvis, and two vertical lines drawn as if dropped from the midpoint of each clavicle collarbone.

There are nine resulting regions. A s erous membrane also referred to a serosa is one of the thin membranes that cover the walls and organs in the thoracic and abdominopelvic cavities. The parietal layers of the membranes line the walls of the body cavity pariet- refers to a cavity wall. The visceral layer of the membrane covers the organs the viscera. Between the parietal and visceral layers is a very thin, fluid-filled serous space, or cavity Figure 1.

There are three serous cavities and their associated membranes. The pleura is the serous membrane that surrounds the lungs in the pleural cavity. The visceral pleura is located on the surface of the lungs, the parietal pleura lines the wall of the thoracic cavity. Figure 1. The pericardium is the serous membrane that surrounds the heart in the pericardial cavity. The visceral pericardium is located on the heart wall, the parietal pericardium lines the wall of the pericardial sac Figure 1.

The peritoneum is the serous membrane that surrounds several organs in the abdominopelvic cavity. The visceral peritoneum lines the surface of many organs, the parietal peritoneum lines the wall of the abdominopelvic cavity.

The serous fluid produced by the serous membranes reduces friction between the walls of the cavities and the internal organs when they move, such as when the lungs inflate or the heart beats. Both the parietal and visceral serosa secrete the thin, slippery serous fluid that prevents friction when an organ slides past the walls of a cavity.

In the pleural cavities, pleural fluid prevents friction between the lungs and the walls of the cavity. In the pericardial sac, pericardial fluid prevents friction between the heart and the walls of the pericardial sac. And in the peritoneal cavity, peritoneal fluid prevents friction between abdominal and pelvic organs and the wall of the cavity.

The serous membranes therefore provide additional protection to the viscera they enclose by reducing friction that could lead to inflammation of the organs. Privacy Policy. Skip to main content. Module 1: Body Plan and Organization. Search for:. Anatomical Terminology Learning Objectives Demonstrate the anatomical position Describe the human body using directional and regional terms Identify three planes most commonly used in the study of anatomy Distinguish between the posterior dorsal and the anterior ventral body cavities, identifying their subdivisions and representative organs found in each Describe serous membrane and explain its function.

Anterior or ventral Describes the front or direction toward the front of the body. Anterior and posterior are sometimes used in place of superior and inferior, respectively.

These words are used more often for animal anatomy and rarely and only with very specific meaning in human anatomy. Anterior refers to the side of the structure facing up in the standard anatomical position while posterior refers to the bottom side.

For example, the pituitary gland has an anterior and posterior side, each of which secretes different types of hormones. Dorsal and ventral are sometimes used in place of anterior and posterior, respectively.

Dorsal means the back side or upper side, while ventral means the frontal or lower side. These are mostly used with animal anatomy, but can be used in human anatomy as long as they are describing the side of an appendage. Lateral is used to describe anything closer to the sides of the body toward the arms, in the standard anatomical position , while medial is used to describe anything toward the middle of the body.

In general, many structures of the human body are bilateral and symmetrical with the middle of the body, such as the lungs or the arms.