Anatomy and Physiology: An Introduction

Understanding Our Bodies

• Importance of appreciating the complexity of simple actions.
• Human body: a collection of systems working together.
• Examples of body complexity:
  • Intestines as long as a three-story building.
  • Enough saliva to fill more than one swimming pool over a lifetime.
  • Loss of skin cells leading to dust mites.

Disciplines of Anatomy and Physiology

• Anatomy: study of the structure and relationships between body parts.
• Physiology: science of how body parts function and keep the body alive.
• These disciplines provide insights into life, disease, and recovery.
• Draws knowledge from chemistry, physics, and other sciences.

Historical Context

• Dissection of bodies was taboo historically.
• Key figures:
  • Galen: Vivisections on pigs.
  • Da Vinci: Anatomical drawings until restricted by the Pope.
  • 17th and 18th centuries: public dissections.
• Anatomy Act of 1832 in Britain regulated access to bodies for study.
• Modern use of educational cadavers for learning anatomy.

Key Concepts

• Complementarity of Structure and Function: What a structure can do depends on its form.
• Body organization from smallest to largest:
  • Atoms
  • Cells
  • Tissues
  • Organs
  • Organ Systems
  • Complete Organisms
• Homeostasis: Maintenance of stable internal conditions.
  • Essential for survival.
  • Imbalance leads to death (e.g., loss of blood pressure).

Anatomical Language

• Importance of precise language in anatomy.
• Anatomical position: standing erect, facing forward, arms at sides.
• Body planes:
  • Sagittal Plane: Divides left and right.
  • Coronal Plane: Divides front and back.
  • Transverse Plane: Divides top and bottom.

Directional Terms

• Anterior (Ventral): Front of the body.
• Posterior (Dorsal): Back of the body.
• Superior (Cranial): Towards the head.
• Inferior (Caudal): Lower parts of the body.
• Medial: Toward the midline.
• Lateral: Away from the midline.
• Proximal: Closer to the trunk.
• Distal: Farther from the trunk.

Conclusion

• Anatomy studies the structure; physiology explains the function.
• Central principles include complementarity, hierarchical organization, and homeostasis.
• Directional terms facilitate precise communication in medicine.