Anatomical Directions and Major Body Regions Anatomical Position and Bilateral Symmetry • In the anatomical position, the body is in an erect, or standing, posture with the arms at the sides and palms forward. The head and feet are also pointing forward. • Bilateral Symmetry – the left and right sides are mirror images of each other, and only one plane can divide the body into left and right sides. Anatomical Position and Bilateral Symmetry • Ipsilateral – on the same side • Contralateral – on the opposite side Major Body Cavities • Dorsal Body Cavity – Cranial cavity – Spinal cavity • Ventral Body Cavity – Thoracic cavity – Abdominopelvic cavity Body Regions • Axial – consists of the head, neck and torso • Appendicular – consists of the upper and lower extremities and their connections to the axial portion Directional Terms • Superior – toward the head • Inferior – toward the feet • Anterior – front or in front of • Posterior – back or in back of • Ventral – toward the belly • Dorsal – toward the back • Medial – toward the midline of the body • Lateral – toward the side of the body, or away from its midline • Proximal – toward the nearest the trunk of the body, or nearest point of origin • Distal – away from or farthest from the trunk or point of origin of a body part • Superficial – nearer the surface • Deep – farther away from the body surface Body Planes • Sagittal – A lengthwise plane running from front to back that divides the body into right and left sides. • Coronal – A lengthwise plane running from side to side. Divides the body or any of its parts into anterior and posterior. Also called a frontal plane. • Transverse – A crosswise plane; divides the body or any of its parts into upper and lower parts. Also called a horizontal plane.