Anatomy & Physiology: Foundations and Terminology

Key Terms and Word Origins

Understanding medical terminology is essential for studying anatomy and physiology. Many terms are derived from Latin or Greek roots, prefixes, and suffixes, which provide clues to their meaning.

• Prefix: Attached to the beginning of a word; indicates location, time, number, or status.

• Suffix: Attached to the end of a word; indicates procedure, condition, disorder.

• Combining form: Used to combine forms; a vowel is used when the next syllable begins with a consonant.

• Abbreviations: Shortened forms of words or phrases (e.g., Dr. for Doctor).

• Acronym: Formed from the initial letters of a phrase (e.g., AIDS).

• Symbol: One or more letters or numbers representing a specific meaning or process.

• Eponym: A word that uses a person's name to describe something (e.g., Parkinson's disease).

Antonyms are words that mean the opposite of each other (e.g., hot/cold). Synonyms are words that mean the same thing (e.g., gallbladder/cholecyst). Homonyms are words that sound the same but have different meanings (e.g., bat (animal) or bat (baseball bat)).

• Plural forms: Words that pluralize the words:

  • For -a: -ae

  • For -us: -i

  • For -ix: -ices

Overview of Anatomy & Physiology

Definition and Scope

Anatomy is the study of the structure of the body and its relationships. Physiology is the study of the function of body parts and systems. Both disciplines are closely linked, as structure often determines function.

Three Types of Anatomy

• Gross anatomy: Anatomy that can be seen, felt, and touched (e.g., heart, lungs, kidneys).

  • Regional anatomy: Structures in one region are examined at the same time (e.g., muscles, bones, blood vessels, nerves).

  • Surface anatomy: Subdivision that emphasizes relationships between external landmarks and deeper internal structures.

  • Systemic anatomy: Deals with structures studied as body systems (e.g., cardiovascular system).

• Microscopic anatomy: Structures too small to be seen with the naked eye.

  • Cytology: Study of cells.

  • Histology: Study of tissues.

• Developmental anatomy: Emphasizes changes throughout our body structure from fertilization to old age.

  • Embryology: Concerns developmental changes that occur before birth.

Physiology: Subdivisions and Principles

Subdivisions of Physiology

• Molecular physiology: Understanding functions at the molecular level.

• Cellular physiology: Functions of cells, focusing on chemical reactions and processes.

• Tissue physiology: Studies how tissues function in the body (e.g., epithelial, CT, muscle, nervous).

• Organ physiology: Study of how organs function within the body.

• Organ system physiology: Study of how organ systems function within the body.

  • Renal physiology: Emphasizes kidney function.

  • Neurophysiology: Emphasizes neural interactions in the nervous system.

  • Cardiovascular physiology: Examines the operation of the heart and blood vessels.

• Organism physiology: Study of how various parts of the organism function and work together.

Principle of Complementarity

The function of a body structure depends on its form. Form follows function, and function follows form. The function always reflects the structure, and what a structure can do depends on its form.

Levels of Structural Organization

Hierarchy of Organization

• Chemical: Atoms (tiny building blocks of matter) combine to form molecules.

• Molecular: Molecules (water, proteins) associate to form organelles (basic components of cells).

• Cellular: The smallest unit of living things.

• Tissues: Formed of similar cells (come together to form organs).

• Organs: Discrete structures composed of at least two kinds of tissues.

• Organ systems: Organs that function together to form organ systems.

• Organism: Living human being, representing the sum of all structural levels working together.

Major Organ Systems of the Human Body

Overview of Eleven Organ Systems

• Integumentary: Skin, hair, nails.

  • Creates a boundary from the external environment.

  • Protects deeper tissues from injury.

  • Synthesizes vitamin D.

  • Regulates body temperature.

  • Houses receptors for touch and pain.

  • Sweat and oil glands.

• Skeletal: Bones, joints.

  • Protects and supports body organs.

  • Provides a framework for muscles to attach to.

  • Manufactures blood cells.

  • Stores minerals such as calcium.

• Muscular: Skeletal muscles, tendons.

  • Allows for manipulation of the environment.

  • Locomotion.

  • Facial expression.

  • Maintains posture.

  • Produces heat.

• Nervous: Brain, spinal cord, nerves, sensory receptors.

  • Fast-acting control system of the body.

  • Responsiveness.

• Endocrine: Hypothalamus, pituitary, pineal, thyroid, parathyroid, thymus, adrenal glands, pancreas, testes, ovaries.

  • Secretes hormones; controls system of the body.

  • Regulates processes such as growth, reproduction, and nutrient use.

• Cardiovascular: Heart, blood vessels, blood.

  • Heart pumps blood.

  • Carries oxygen and nutrients to organs and removes wastes and carbon dioxide.

• Lymphatic/Immune: Lymph nodes, lymphatic vessels, spleen, thymus, bone marrow.

  • Picks up leaked fluid from blood vessels and returns it to the blood.

  • Protects from invaders and mounts a response to infection.

• Respiratory: Lungs, nasal cavity, pharynx, larynx, trachea, bronchi, diaphragm.

  • Supplies oxygen to the blood.

  • Removes carbon dioxide from the blood.

  • Gas exchange occurs in the lungs.

• Digestive: Oral cavity, esophagus, stomach, small and large intestines, liver, gall bladder, pancreas.

  • Moves food through the GI tract.

  • Eliminates undigested food as feces.

• Urinary: Kidneys, ureters, urinary bladder, urethra.

  • Regulates water, electrolyte, and acid-base balance.

• Reproductive: Male: prostate, vas deferens, penis, testes. Female: ovaries, oviduct, uterus, vagina.

  • Production of offspring.

Essential Life Functions

Survival Needs and Processes

• Maintaining boundaries: Plasma membrane, skin; protects from external environment.

• Movement: Muscles contract to move body parts.

• Responsiveness: Ability to sense and respond to stimuli.

• Digestion: Breakdown of ingested foodstuffs.

• Metabolism: All chemical reactions in the body.

  • Catabolism: Breakdown of molecules.

  • Anabolism: Synthesis of molecules.

  • Uses nutrients and oxygen to produce ATP through cellular respiration.

• Excretion: Removal of wastes from metabolism and digestion.

• Reproduction: Production of offspring; cell division for growth and repair.

• Growth: Increase in size of the organism; constructive activities must outpace destructive ones.

Survival Needs

• Nutrients

• Oxygen

• Water

• Normal body temperature

• Appropriate atmospheric pressure

Directional Terms and Body Organization

Directional Terms

• Superior: Towards the head

• Caudal: Towards the feet

• Medial: To the middle

• Lateral: To the side

• Anterior (ventral): Towards the front

• Posterior (dorsal): Towards the back

• Superficial: Closer to the surface

• Deep: Further from the surface

• Contralateral: On the opposite side

• Ipsilateral: On the same side

• Axial: The head, spine, and trunk

• Appendicular: The limbs

Body Planes

• Sagittal plane: Vertical plane dividing the body into right and left parts.

  • Midsagittal/median plane: Divides the body or organ along the midline.

  • Parasagittal plane: Divides off the midline.

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

• Transverse (horizontal) plane: Divides the body into superior and inferior parts; also called cross-section.

• Oblique sections: Cuts made diagonally between the horizontal and vertical planes.

Body Cavities

• Dorsal body cavity: Protects the nervous system; subdivided into:

  • Cranial cavity: Encloses the brain.

  • Vertebral cavity: Encloses the spinal cord.

• Ventral body cavity: Houses internal organs; subdivided into:

  • Thoracic cavity: Contains two pleural cavities, pericardial cavity (encloses the heart), and mediastinal cavity.

  • Abdominopelvic cavity: Subdivided into abdominal cavity and pelvic cavity.

The diaphragm separates the superior thoracic cavity from the inferior abdominopelvic cavity. The serous membrane allows organs to move and pump, such as the heart, while decreasing friction.

Abdominopelvic Regions

Nine Regions and Their Organs

Additional info:

• Some content was expanded for clarity and completeness, such as definitions and examples of anatomical terms, and the organization of organ systems.

• Tables were recreated from the original images and text, with logical inferences where necessary.