Chapter 1: An Introduction to Anatomy - Vocabulary Flashcards

Introduction to Anatomy

• Core idea: Structure determines function; all specific functions are performed by specific structures.
• Key takeaway: Structure, therefore, determines function.
• This unit provides foundational concepts for understanding how the body is organized and studied.

Microscopic Anatomy

• Definition: Structures that cannot be seen without magnification.
• Limitations: Limited by the equipment used.
• Key sub-disciplines:
  • Cytology — the study of cells
  • Histology — the study of tissues
• Common tools:
  • Light microscope
  • Electron microscope

Gross Anatomy

• Definition: The study of structures visible to the unaided eye (macroscopic anatomy).
• Sub-divisions:
  • Surface anatomy: general form, morphology, and superficial markings.
  • Regional anatomy: all structures in a specific area (superficial or deep).
  • Systemic anatomy: study of anatomy one organ system at a time.

Other Perspectives on Anatomy

• Developmental anatomy: examines structural changes over time.
• Embryology: study of the first two months of development.
• Comparative anatomy: compares different animals.
• Clinical anatomy: focuses on pathological changes during illness.
• Surgical anatomy: studies anatomical landmarks important for surgical procedures.
• Radiographic anatomy: anatomy as visualized by x-rays, ultrasound, and other imaging on an intact body.
• Cross-sectional anatomy: uses graphs from CT/MRI to view body sections.

More on Comparative Anatomy

• Figures illustrate comparative anatomy concepts (differs across species).

Levels of Organization

• Chemical/Molecular level:

  • 12+ elements in the body.
  • The four that make up about 99% of the body mass: H, O, C, N.
  • Major classes of compounds: Water, Carbohydrates, Proteins, Lipids, Nucleic acids.

• Elemental and molecular composition (visuals summarized):

  • a) Elemental composition: primary elements and trace elements (as depicted in Fig. 1.1). Example major components and trace elements include elements such as Oxygen, Carbon, Hydrogen, Nitrogen, Calcium, Phosphorus, Potassium, Sodium, Magnesium, Chlorine, Iron, Iodine, and other trace elements.
  • b) Molecular composition: distribution of Water, Proteins, Lipids, Carbohydrates, Nucleic acids, etc.

• Biological organization hierarchy (from simple to complex):

  • Chemical or Molecular level
  • Cellular level
  • Tissue level
  • Organ level
  • Organ system level
  • Organism level

• The human is composed of 11 organ systems.

• Diagrammatic progression (high to low): Organism → Organ System → Organ → Tissue → Cell → Molecule → Atom.

The 11 Organ Systems and Their Major Functions

• Integumentary system: Protection from environmental hazards; temperature control.

• Skeletal system: Support; protection of soft tissues; mineral storage; blood formation.

• Muscular system: Locomotion; support; heat production.

• Nervous system: Directs immediate responses to stimuli; coordinates activities of other organ systems.

• Endocrine system: Directs long-term changes in activities of other organ systems.

• Cardiovascular system: Internal transport of cells and dissolved materials (nutrients, wastes, gases).

• Lymphoid (Lymphatic) system: Defense against infection and disease; returns tissue fluid to the bloodstream.

• Respiratory system: Delivery of air to sites of gas exchange between air and blood.

• Digestive system: Processing of food and absorption of nutrients, minerals, vitamins, and water.

• Urinary system: Elimination of excess water, salts, and waste products; pH regulation.

• Reproductive system: Production of sex cells and hormones; (in females) supports embryonic development from fertilization to birth.

• Note on the male and female reproductive systems:

  • Male: Prostate gland, seminal glands, ductus deferens, epididymis, testis, penis, scrotum.
  • Female: Mammary glands, uterine tube, ovary, uterus, vagina, external genitalia.

Integumentary and Skeletal/Muscular/Nervous Systems (Illustrated Examples)

• Integumentary system components: hair, epidermis with glands, fingernails.
• Axial skeleton components: skull, sternum, ribs, vertebrae.
• Appendicular skeleton components: scapula, clavicle, upper limb bones; pelvic bones; lower limb bones.
• Muscular system: axial and appendicular muscles; central nervous system controls and coordinates movement.
• Nervous system: brain and spinal cord (central nervous system) and peripheral nerves (peripheral nervous system).

Endocrine and Cardiovascular Systems (Illustrated Elements)

• Endocrine glands shown: pineal gland, pituitary gland, parathyroid glands, thymus, thyroid, suprarenal (adrenal) gland, pancreas, ovary, testis.
• Cardiovascular components: heart, capillaries, arteries, veins; pathways of internal transport of nutrients, wastes, and gases.

The Lymphoid, Respiratory, Digestive, and Urinary Systems (Illustrated Elements)

• Lymphoid: lymph nodes, thymus, lymph vessels; defense against infection and disease; returns tissue fluid to the bloodstream.
• Respiratory: trachea, bronchi, lungs; gas exchange regions.
• Digestive: liver, stomach, small and large intestine, pancreas, salivary glands, gallbladder; digestion and nutrient absorption.
• Urinary: kidneys, ureters, urinary bladder, urethra; elimination of wastes; regulation of water, salts, and pH.

The Male and Female Reproductive Systems (Overview)

• Male: Ducts and glands that produce, transport, and temporarily store sperm; prostate, seminal glands, ductus deferens, epididymis, testis, penis, scrotum.
• Female: Ovaries produce eggs and hormones; uterus, uterine tubes, vagina; mammary glands support offspring after fertilization.

The Language of Anatomy

• Superficial Anatomy: anatomical landmarks and directional terms help locate deeper structures.
• Anatomical landmarks and positions:
  • Anatomical position: standing upright, arms at sides, palms facing forward, feet flat, face forward.
  • Supine: lying on the back.
  • Prone: lying on the stomach.

Anatomical Landmarks and Positioning (Figures 1.x)

• Anatomical landmarks are used to describe precise locations on the body.
• Key reference position is the anatomical position for consistency across descriptions.

Planes of Section and Planes Discussion (Table 1.3 and Figures 1.11–1.12)

• Planes of section (orientation relative to body):
  • Transverse (or horizontal): perpendicular to the long axis; separates superior and inferior portions.
  • Sagittal: runs parallel to the long axis; separates right and left portions.
  • Midsagittal: a sagittal plane that passes through the midline, dividing body into equal right and left halves.
  • Parasagittal: sagittal plane that misses the midline, producing unequal right and left portions.
  • Frontal (coronal): separates anterior and posterior portions; usually refers to sections through the skull.
• Descriptions for planes: components and direction terms relative to the long axis.

Sectional Anatomy and Body Cavities

• Sectional anatomy: a method to illustrate relationships between parts of three-dimensional objects.
• Modern imaging (CT, MRI) allows visualization inside the living body without surgery.
• Body planes and body cavities help organize anatomical study.
• Ventral body cavity: houses organs of respiratory, cardiovascular, digestive, urinary, and reproductive systems.
• The diaphragm divides the ventral body cavity into thoracic and abdominopelvic cavities.
• Serous membranes: two-layer membrane system that protects and lubricates the ventral cavity organs.
• Planes and sections help visualize cross-sections of organs and cavities.

Ventral Body Cavities and Membranes (Figure references)

• Posterior and anterior body cavity organization (visuals show Pleural, Pericardial, and Abdominopelvic cavities).
• Thoracic cavity contains:
  • Pleural cavities surrounding each lung with visceral and parietal pleura.
  • Pericardial cavity surrounding the heart with pericardium (visceral and parietal layers).
  • Mediastinum region within the thoracic cavity.
• Abdominopelvic cavity contains abdominal and pelvic regions separated by the diaphragm.
• The peritoneal cavity (within the abdominal cavity) is lined with parietal and visceral peritoneum.

Regions and Directional Terms (Tables 1.1 and 1.2)

• Table 1.1 Regions of the Human Body (examples and names):
  • Cephalon: Cephalic region of the head; Cervicis: Cervical region (neck).
  • Thoracis: Thoracic region (chest).
  • Brachium: Upper arm (brachial region).
  • Carpus: Wrist; Manus: Hand; Abdomen: Abdominal region; Pelvis: Pelvic region; Pubis: Pubic region; Inguen: Inguinal region (groin).
  • Lumbus: Lumbar region (lower back); Gluteus: Gluteal region (buttock).
  • Femur: Femoral region (thigh); Patella: Patellar region (kneecap).
  • Crus: Crural region (leg from knee to ankle); Sura: Sural region (calf).
  • Tarsus: Tarsal region (ankle); Pes: Pedal region (foot); Planta: Plantar region (sole).
• Table 1.2 Regional and Directional Terms:
  • Anterior (Ventral): The front of the body; e.g., navel on the anterior surface.
  • Posterior (Dorsal): The back of the body; e.g., scapula behind the rib cage.
  • Cranial (Cephalic): Toward the head (same as superior in humans).
  • Superior (Cranial): Above; toward the head.
  • Inferior (Caudal): Below; toward the feet.
  • Medial: Toward the midline of the body.
  • Lateral: Away from the midline.
  • Proximal: Near a point of attachment.
  • Distal: Farther from the attachment.
  • Superficial: Toward the surface.
  • Deep: Away from the surface.
• Examples provided in the table illustrate how these terms are used in describing location (e.g., scapula is posterior to rib cage; knee is distal to hips).

Planes of Section – Summary (Figure 1.11 and Table 1.3)

• Relationship of planes to body orientation:
  • Transverse planes cut horizontally; separate superior and inferior portions.
  • Sagittal planes cut lengthwise; separate left and right portions.
  • Midsagittal plane divides body into equal left and right halves.
  • Parasagittal plane divides body into right and left portions that are not equal.
  • Frontal (coronal) planes separate anterior from posterior portions.
• When describing cuts, use terms such as sagittally, frontal, or transversely depending on the plane.

Body Cavities and Serous Membranes (Summary)

• The ventral body cavity contains organs of the digestive, urinary, reproductive, cardiovascular, and respiratory systems.
• The diaphragm is the major muscle that separates the thoracic cavity from the abdominal cavity.
• Serous membranes form two-layer protective coverings:
  • Parietal layer lining the cavity wall.
  • Visceral layer covering the organs.
  • A serous cavity with serous fluid sits between layers to reduce friction.

Quick Reference: Connective Dots to Foundational Principles

• Foundational principle: Structured organization (atoms → molecules → cells → tissues → organs → organ systems → organism) enables complex functions and emergent properties.
• Cross-disciplinary relevance: Radiographic anatomy bridges clinical practice with anatomy; understanding planes and cavities is essential for imaging interpretation and surgical planning.
• Ethical/philosophical note: Knowledge of anatomy underpins medical practice, patient care, and informed consent in procedures that involve the body.

Mathematical/Quantitative Notes

• Elements and compounds overview:
  • The body contains 12+ essential elements; 4 major elements constitute about 99% of body mass: ext{H}, ext{O}, ext{C}, ext{N}.
  • Major classes of compounds: Water, Carbohydrates, Proteins, Lipids, Nucleic acids.
• Conceptual percentages (summary from organizational figures):
  • Water is a dominant component (roughly two-thirds of body mass).
  • Carbohydrates, proteins, and lipids are present in smaller but significant portions.
  • Nucleic acids are present in smaller quantities relative to water and macromolecules.
  • Trace elements (e.g., Ca, P, K, Na, Mg, Cl, Fe, I) are present in small percentages but are essential for function.

End of Notes