Introduction to the Human Body

Overview of Anatomy

Importance of Studying Anatomy

• Essential for health professions (physicians, nurses, athletic trainers, etc.)
• Useful for maintaining physical fitness and understanding personal health
• Facilitates effective communication with healthcare providers

Anatomy vs. Physiology

• Anatomy: Study of the structure/form of the human body (e.g., identifying body parts)
• Physiology: Study of body function (e.g., how body parts operate)
• Structure and function are interrelated; function follows structure

Example:

• Eye
  • Cornea: Transparent structure allowing light passage, aiding vision

Levels of Anatomical Study

1. Chemical Level: Atoms and molecules
2. Cellular Level: Basic unit of life, includes cell membranes
3. Tissue Level: Groups of similar cells
4. Organ Level: Structures composed of different tissue types
5. Organ System Level: Groups of organs that perform specific functions
6. Organismal Level: The entire human body as a functioning whole

Metric System in Anatomy

• Length
  • Meter (
  • Centimeter (cm): 1/100th of a meter
  • Micrometer (µm): 1/1,000,000th of a meter
• Volume
  • Liter (L)
  • Milliliter (mL): 1/1,000th of a liter
• Mass
  • Gram (g)
  • Kilogram (kg): 1,000 grams

Anatomical Nomenclature

• Derived from ancient Greek and Latin
• Standardized for consistency globally
• Examples: Arm (Brachium), Thigh (Femur)

Gross Anatomy

Definition

• Study of structures visible to the naked eye
• Different from microscopic anatomy (which requires a microscope)

Approaches to Gross Anatomy

• Regional Anatomy: Study of specific regions (e.g., head, neck)
  • Commonly used in medical school and by surgeons
• Systemic Anatomy: Study of the body's systems (e.g., cardiovascular system)
  • Ideal for undergraduate education
• Surface Anatomy (mentioned): Using external markings to infer underlying structures

Body's Organ Systems and Their Major Functions

• Identify and understand basic functions of the major organ systems (e.g., cardiovascular, respiratory)

Anatomical Position and Directions

Anatomical Position

• Standardized body orientation for reference
  • Feet flat, toes forward, palms forward
  • Right and left are from the perspective of the subject

Directional Terms

• Anterior (ventral): Front
• Posterior (dorsal): Back
• Superior: Towards the head
• Inferior: Towards the feet
• Medial: Towards the midline
• Lateral: Away from the midline
• Proximal: Closer to trunk/point of attachment
• Distal: Further from trunk/point of attachment
• Ipsilateral: Same side
• Contralateral: Opposite side
• Superficial: Towards the surface
• Deep: Away from the surface

Anatomical Planes and Sections

• Sagittal Plane: Divides body into left and right
• Frontal (Coronal) Plane: Divides body into front and back
• Transverse Plane: Divides body into upper and lower parts

Human Body Plan Highlights

• Tube-within-a-tube: Digestive system and outer body
• Bilateral Symmetry: Symmetrical left and right sides
• Dorsal Hollow Nerve Cord: Develops into brain and spinal cord
• Notochord: Seen in embryonic stage, replaced by vertebral column
• Segmentation: Repeating units (e.g., vertebrae, ribs)
• Pharyngeal Pouches: Develop into inner ear structures and parathyroid glands

Body Cavities and Serous Membranes

• Cranial Cavity: Contains brain
• Vertebral Cavity: Contains spinal cord
• Thoracic Cavity: Contains heart and lungs
• Abdominal Cavity: Contains digestive organs
• Pelvic Cavity: Contains urinary and reproductive organs
• Serous Cavities: Double-membraned structures (e.g., pleura in lungs)

Application in Clinical Diagnosis

• Surface Anatomy: Used to diagnose and treat based on external landmarks
• Quadrants of the abdomen for locating internal issues (e.g., liver, gallbladder)

Summary

• Understand learning objectives for this lecture
• Overview of anatomy and gross anatomy, key concepts, and terminologies