Anatomy and Anatomical Terminology

Introduction and Anatomical Terminology

• Anatomy:

  • Derived from Greek words "ana" (apart) and "tomy" (to cut).

  • Definition: The study of body structure.

  • The word "tomy" means "to cut" or "dissect."

  • Involves putting things back together or understanding them in slices.

• Subdivisions of Anatomy:

  • Surface Anatomy: Study of form and markings on the body surface.

  • Gross (Macroscopic) Anatomy: Study of structures that can be examined without a microscope.

  • Systemic Anatomy: Study of specific organ systems (e.g., digestive system).

  • Regional Anatomy: Study of specific regions of the body (e.g., head or chest).

  • Radiographic Anatomy: Study using X-rays.

  • Developmental Anatomy: Study of development from fertilized egg to adult form.

  • Embryology: Study of development from fertilized egg through the eighth week in utero.

  • Histology: Microscopic study of tissues.

  • Cytology: Microscopic study of cells.

  • Pathological Anatomy: Study of structural changes associated with disease.

Physiology

• Definition: The science of body functions.

  • The word "physis" means "nature."

• Includes the study of homeostasis.

  • Homeostasis: Keeping the organs and systems of the body in balance.

Relationship Between Anatomy and Physiology

• Anatomy and physiology are interconnected.

• Each structure has a specific function.

• They are studied together to understand the relationship between structure and function.

• Examples:

  • Differences between the female and male pelvis for childbirth.

  • Bone features:

    • Arches, femur, and vertebral column: Curves for shock absorption.

    • Spinous and transverse processes: Projections for muscle attachment.

    • Foramen: Allows passage for nerves, blood vessels, or other structures.

Levels of Structural Organization (Simplest to Most Complex)

1. Atom

   • Smallest unit of matter.

   • Composed of protons, neutrons, and electrons.

   • Visualized only with an electron microscope (fuzzy image).

   • Atoms that comprise 96% of the human body (greatest to least quantity):

     • Oxygen (O)

     • Carbon (C)

     • Hydrogen (H)

     • Nitrogen (N)

2. Molecule

   • Combination of two or more atoms (same or different) bonded together.

   • Examples: Oxygen (O2), water (H2O)

3. Compound

   • Combination of two or more molecules bonded together.

   • Examples:

     • Protein (formed from amino acid molecules).

     • Carbohydrate (formed from sugar molecules).

     • Fat or lipid (formed from glycerol and fatty acid molecules).

     • Nucleic acids DNA & RNA (formed from nucleotide molecules).

4. Organelle

   • Tiny structures within cells that carry out specialized cell functions.

   • Examples:

     • Mitochondrion: Produces energy.

     • Lysosome: Destroys bacteria that enter the cell.

5. Cell

   • Smallest living unit of structure and function of the body.

   • Composed of organelles.

   • Examples:

     • Muscle cell.

     • Nerve cell.

6. Tissue

   • A group of similar (not necessarily identical) cells plus their intercellular material (matrix) that carry out a particular function.

   • 4 basic tissues of the body:

     • Epithelium

     • Connective

     • Muscle

     • Nervous

7. Organ

   • Structure composed of two or more different tissues carrying out a specific function.

   • Has a recognizable shape.

   • Example: Heart.

8. Organ System

   • Related organs that work together to carry out a particular function.

   • Example: Cardiovascular system.

9. Organism

   • All the organ systems working together to compose a living individual.

   • Example: Human being.

Organ Systems (11)

• Integumentary System

  • Components: Hair, skin, nails.

  • Functions: Encloses internal body structures and is the site of many sensory receptors.

• Skeletal System

  • Components: Joints, cartilage, and bones.

  • Functions: Supports the body and enables movement (with the muscular system).