Introduction to Anatomy

• Anatomy is the study of the structure of living organisms
• It includes the location, size, shape, and relationships of body parts

Levels of Anatomical Study

• Gross Anatomy: Study of structures visible to the naked eye

• Includes regional, systemic, and surface anatomy

• Microscopic Anatomy: Study of structures at the microscopic level

• Includes cytology (study of cells) and histology (study of tissues)

• Developmental Anatomy: Study of structural changes from conception to adulthood

• Includes embryology (study of development before birth)

Regional Anatomy

• Focuses on specific regions of the body (e.g., head, thorax)
• Examines all structures within that region
• Useful for understanding clinical conditions in a specific area

Systemic Anatomy

• Focuses on the body's organ systems (e.g., skeletal, nervous)
• Studies the structure and function of each system individually
• Provides a comprehensive view of how systems work together

Surface Anatomy

• Studies internal structures as they relate to the skin surface
• Used for physical examination and identifying landmarks

Cytology

• Studies the structure and function of individual cells
• Examines organelles, cell membranes, and cellular processes

Histology

• Studies the structure and organization of tissues
• Identifies tissue types (e.g., epithelial, connective, muscle, nervous)
• Examines how cells are arranged and specialized

Embryology

• Studies the development of an organism from fertilization to birth
• Examines organ formation and potential developmental abnormalities

Anatomical Terminology

• Anatomical Position: Standard reference point

• Body erect, feet slightly apart, palms facing forward

• Superior (cranial): Toward the head

• Inferior (caudal): Toward the feet

• Anterior (ventral): Toward the front

• Posterior (dorsal): Toward the back

• Medial: Toward the midline

• Lateral: Away from the midline

• Proximal: Closer to the origin or point of attachment

• Distal: Farther from the origin or point of attachment

• Superficial (external): Toward the surface

• Deep (internal): Away from the surface

Anatomical Planes

• Sagittal Plane: Divides the body into left and right parts

• Midsagittal (median) plane: divides the body into equal left and right halves

• Parasagittal plane: offset from the midline

• Frontal (coronal) Plane: Divides the body into anterior and posterior parts

• Transverse (horizontal) Plane: Divides the body into superior and inferior parts

Body Cavities

• Dorsal Body Cavity: Located near the posterior surface of the body

• Cranial cavity: contains the brain

• Vertebral cavity: contains the spinal cord

• Ventral Body Cavity: Located near the anterior surface of the body

• Thoracic cavity: contains the heart and lungs

• Pleural cavities: each surrounds a lung

• Mediastinum: contains the heart, esophagus, and trachea

• Abdominopelvic cavity: contains the abdominal and pelvic organs

• Abdominal cavity: contains the stomach, intestines, liver, and other organs

• Pelvic cavity: contains the bladder, reproductive organs, and rectum

Membranes of Body Cavities

• Serous Membranes: Line the ventral body cavity and cover organs

• Parietal serosa: lines the cavity walls

• Visceral serosa: covers the organs

• Serous Fluid: Separates the parietal and visceral serosae

  • Reduces friction as organs move

• Specific Serous Membranes:

  • Pleura: surrounds the lungs
  • Pericardium: surrounds the heart
  • Peritoneum: surrounds the abdominal organs

Skeletal System

• Provides support, protection, and movement
• Bones, cartilage, ligaments, and joints

Muscular System

• Enables movement, maintains posture, and generates heat
• Skeletal muscles, smooth muscles, and cardiac muscle

Nervous System

• Controls and coordinates bodily functions
• Brain, spinal cord, and nerves

Endocrine System

• Regulates body functions through hormones
• Glands such as the pituitary, thyroid, and adrenal glands

Cardiovascular System

• Transports blood, oxygen, and nutrients
• Heart, blood vessels, and blood

Lymphatic System

• Returns fluids to the bloodstream and provides immunity
• Lymph nodes, lymphatic vessels, and lymphoid organs

Respiratory System

• Exchanges gases (oxygen and carbon dioxide)
• Lungs, trachea, and bronchi

Digestive System

• Breaks down food and absorbs nutrients
• Mouth, esophagus, stomach, intestines, liver, and pancreas

Urinary System

• Filters waste from the blood and eliminates it as urine
• Kidneys, ureters, bladder, and urethra

Reproductive System

• Enables reproduction
• Male: testes, penis, and associated structures
• Female: ovaries, uterus, vagina, and associated structures

Anatomical Variation

• Individuals can have slight variations in anatomy
• Variations can be due to genetics, environment, or disease

Clinical Significance

• Understanding anatomy is crucial for diagnosing and treating diseases
• Anatomical knowledge guides surgical procedures and medical interventions