Planes of the Body

• Coronal Plane, divides the body into front and rear sections. Also called the frontal plane.
• Frontal plane, divides the body into front and rear sections. Also called the coronal plane.
• Horizontal Plane, divides the body into a superior (or upper) and an inferior (or lower) section. Also called the transverse plane.
• Median Plane, divides the body into right and left halves. Also called the midsagittal plane.
• Midsagittal Plane, divides the body into right and left halves. Also called the median plane.
• Transverse Plane, divides the body into a superior (or upper) and an inferior (or lower) section. Also called the horizontal plane.

Direction and Location

• Anterior, front side of the body, also known as ventral.
• Caudal, in quadrapeds, the tail end [see inferior].
• Cranial, above or near the head, also known as superior.
• Distal, farthest end from the trunk or head.
• Dorsal, back side of the body, also known as the posterior.
• Inferior, below also, toward the feet.
• Infra-, prefix meaning below or under.
• Lateral, away from the midline.
• Medial, toward the midline.
• Posterior, back side of the body, also known as the dorsal.
• Proximal, closest part nearest the trunk or head.
• Superior, above or near the head, also known as cranial.
• Supra-, prefix meaning above or over.
• Ventral, front side of the body, also known as anterior.

Parts of the Human Skull

• Calvarium, includes the brain case.
• Cranium, includes the face and the calvarium.
• Mandible, the lower jaw.
• Skull, includes both the cranium and mandible.

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Bones of the Skull

• Ethmoid bone, sieve-like spongy bone located in the anterior part of the floor of the cranium between the orbits. The ethmoid is the principal supporting structure of the nasal cavity.
• Frontal bone, forms the forehead, the roofs of the orbits, and most of the anterior part of the cranial floor.
• Inferior Nasal Conchae, one of three scroll-like bones that project from the lateral wall of the nasal cavity. The inferior nasal conchae articulate with the ethmoid, maxilla, lacrimal and paltine bones and form the lower part of the lateral wall of the nasal cavity.
• Lacrimal bone, a thin scalelike bone, roughly resembling a fingernail in size and shape, at the anterior part of the medial wall of the orbit, articulating with the frontal and ethmoidal bones and the maxilla and inferior nasal concha.
• Mandible, the bone forming the lower jaw; the largest and strongest bone of the face, presenting a body and a pair of rami, which articulate with the skull at the tempromandibular joints.
• Maxillae, paired bones uniting to form the upper jawbone. The maxillae articulate with every bone of the face except the mandible, or lower jawbone.
• Nasal bone, small oblong bones that meet at the middle and superior part of the face. Their fusion forms the superior part of the bridge of the nose.
• Occipital bone, a single trapezoid-shaped bone situated at the posterior and inferior part of the cranium.
• Palatine bone, one of two irregularly shaped bones (L-shaped) forming the posterior part of the hard palate, the lateral wall of the nasal fossa between the medial pterygoid plate and the maxilla, and the posterior part of the floor of the orbit. The posterior part of the hard palate, which separates the nasal cavity from the oral cavity, is formed by the horizontal plates.
• Vomer, a roughly triangular bone that forms the inferior and posterior of the nasal septum.
• Parietal bones, one of the two quadrilateral bones on either side of the cranium forming part of the superior and lateral surfaces of the skull, and joining each other in the midline at the sagittal suture. The parietal bones form the greater portion of the sides and roof of the cranial cavity.
• Sphenoid bone, a single, irregular, wedge-shaped bone at the base of the skull, which forms a part of the floor of the anterior, middle, and posterior cranial fossae. This bone is referred to as the keystone of the cranial floor because it articulates with all the other cranial bones.
• Temporal bone, one of the two irregular bones on either side of the skull forming part of the lateral surfaces and base of the skull, and containing the organs of hearing. The temporal bones form the inferior sides of the cranium and part of the cranial floor.
• Zygomatic bone, the triangular bones on either side of the face below the eyes, commonly referred to as the cheekbones, they form the prominences of the cheeks and part of the outer wall and floor of the orbits.

Bone Morphology

• Crest, a narrow prominent ridge.
• Condyle, a smooth rounded projection for articulation with another bone.
• Epiphysis, the end of a long bone that is originally separated from the main bone by a layer of cartilage but that later becomes united to the main bone through ossification [compare to suture and symphysis].
• Foramen, a true hole in the bone [e.g. foramen magnum, incisive foramen.
• Line, a narrow raised ridge.
• Meatus, a small tubular opening.
• Sulcus, a groove.
• Suture, the line formed by the junction of two bones or an immovable joint between two bones, especially of the skull [compare to epiphysis and symphysis].
• Symphysis, the line or junction formed by a cartilaginous articulation between two bones without an intervening synovial membrane, this articulation often fuses as in the two bones and the two halves of the mandibles [compare to suture and epiphysis].
• Trochanter, a large rounded projection for muscle attachment.

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