Human Anatomy - H. I. Koliadenko 2009

Main periods and stages of human development in ontogeny
Basic concepts and terms used in anatomy

The horizontal axis and its corresponding plane are parallel to the horizon, dividing the body into upper and lower parts, whereas the frontal axis is parallel to the forehead, dividing the body into anterior and posterior parts.

The sagittal, or median, plane runs perpendicular to the frontal plane and divides the body into right and left halves.

Movements of flexion (flexio) and extension (extensio) occur around the horizontal axis. Movements around the sagittal axis include abduction (abductio) and adduction (adductio).

In addition, specific terms are used to indicate the Location of Organs and the direction of body parts.

Medial (medialis) is located closer to the median plane.

Lateral (lateralis) means positioned away from the median plane to the side.

Cranial (cranialis) refers to structures closer to the HEAD.

Caudal (caudalis) refers to structures closer to the tail end of the body.

Ventral (ventralis) faces toward the anterior abdominal surface.

Dorsal (dorsalis) is the back-facing surface oriented toward the rear.

Proximal (proximalis) is situated closer to the upper part of the trunk.

Distal (distalis) is closer to the lower part of the trunk.

Anterior (anterior).

Posterior (posterior).

Superior (superior).

Inferior (inferior).

External (externus). Internal (internus). Right (dexter).

Left (sinister).

Deep (profundus). Superficial (superficialis).



Last update: 08/08/2026

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