Unit 1, Lesson 8
Lesson 8 - Anatomical Terms 1
Student Performance Objectives
1. Describe the anatomical position for a human and for a cat or rat.
2. Define and give an example for each of the following pairs of terms: anterior-posterior,
superior-inferior, ventral-dorsal, proximal-distal, medial-lateral, superficial-deep,
cephalad-caudad.
3. Explain why these terms are called relative terms.
Lesson Outline
A. The Anatomical Position - this is the human body's reference position in which
the body is upright, head facing forward, arms at the sides with palms facing forward,
and legs slightly apart. All references to the anatomical relationships of parts of
the human body, surface and interior, are made with this position of the body in mind.
B. Relative Positions, their common meanings, and examples.
1. Anterior-posterior: front-back. The eyes, nose and mouth are located on the
anterior surface of the head. Your buttocks are located on the posterior surface of
your pelvic region.
2. Superior-inferior: top-bottom. Your forehead is superior to your eyes. Your
eyes are inferior to your forehead. Your diaphragm is superior to your liver. Your
liver is inferior to your diaphragm.
3. Ventral-dorsal: side opposite backbone-side possessing the backbone. Your vertebral
column is located on the dorsal (or posterior) region of your trunk. Your navel is
located on the ventral (or anterior) region of your trunk. For an animal that walks
on four legs like a horse or a cat or rat, the ventral or belly surface is inferior
(not anterior as in a human); the dorsal surface of a cat is also its superior surface
(not posterior, as in a human). This is because the anatomical or natural position
for a four-legged animal is down on all its legs.
4. Proximal-distal: nearer a point of attachment-further from a point of attachment.
The hand is at the distal end of your arm. Your hand is distal to the wrist. Your
wrist is proximal to your hand. The shoulder is at the most proximal end of your arm.
5. Medial-lateral: nearer to the midline - further from the midline. Your nose
is medial to your cheeks. Your cheeks are lateral to your nose.
6. Superficial-deep: nearer to the surface - further from the surface. Your subcutaneous
fat is deep to the skin. Your skin is superficial to your subcutaneous fat layer.
7. Cephlad-caudad: nearer to the head - further from the head. If you make an incision
on a rats belly from its lower pelvic area up toward the thoracic cavity, the cut
is proceeding in the cephalad direction. A cut downward from the diaphragm toward
the pelvic region is proceeding in a caudad direction.
C. Utilize examples to write a brief essay explaining why these terms are called relative terms.
Biomedical Terminology:
Anterior
Caudad
Cephalad
Deep
Distal
Dorsal
Inferior
Lateral
Medial
Posterior
Proximal
Superior
Ventral