Overview
This lecture introduces the anatomical position, key directional and regional terminology used in human anatomy, and emphasizes the importance of learning these terms for future study.
Anatomical Position
- Anatomical position: standing upright, feet shoulder-width apart, palms forward, thumbs outward.
- All anatomical terminology is based on the body being in this standard position.
Directional Terms
- Directional terms describe locations of body structures relative to one another.
- Terms are usually used in pairs of opposites.
Superior & Inferior
- Superior: toward the top (e.g., head is superior to feet).
- Inferior: toward the bottom (e.g., feet are inferior to head).
Anterior & Posterior (Ventral & Dorsal)
- Anterior: toward the front of the body; Posterior: toward the back.
- In humans, anterior = ventral (belly side), posterior = dorsal (back side).
- In animals that do not walk upright, anterior/posterior and ventral/dorsal differ.
Medial, Lateral, & Intermediate
- Medial: toward the midline; Lateral: away from the midline.
- Example: neck is medial to shoulders; shoulders are lateral to neck.
- Intermediate: between two structures (e.g., heart is intermediate to lungs).
Proximal & Distal
- Used mainly for limbs: Proximal = closer to trunk; Distal = farther from trunk.
- Example: elbow is proximal to wrist; fingers are distal to wrist.
Superficial & Deep
- Superficial: toward body surface (e.g., skin is superficial to muscles).
- Deep: toward the interior (e.g., heart is deep to ribs).
Body Divisions: Axial & Appendicular
- Axial: head, neck, and trunk.
- Appendicular: limbs (arms and legs).
- Arms and legs have further subregions (e.g., arm = shoulder to elbow).
Regional Terms
- Regional terms specify particular areas on the body (e.g., frontal, femoral, calcaneal).
- These terms are foundational for naming bones, muscles, and blood vessels.
- Memorizing regional terms makes understanding anatomical names easier.
Key Terms & Definitions
- Anatomical Position — standard body position for anatomical reference.
- Superior — toward the top of the body.
- Inferior — toward the bottom of the body.
- Anterior (Ventral) — front of the body.
- Posterior (Dorsal) — back of the body.
- Medial — toward the midline of the body.
- Lateral — away from the midline.
- Intermediate — between two structures.
- Proximal — closer to the trunk (in limbs).
- Distal — farther from the trunk (in limbs).
- Superficial — near the surface of the body.
- Deep — further from the surface; more internal.
- Axial — head, neck, and trunk region.
- Appendicular — limbs (arms and legs).
Action Items / Next Steps
- Review and begin memorizing both anterior and posterior regional terms.
- Prepare for an in-class activity practicing these terms next Wednesday.
- Expect a short five-point quiz on these terms next Friday.