INTRO TO ANATOMY & PHYSIOLOGY

Anatomy vs. Physiology

  • Anatomy: Study of the structure of the body

  • Physiology: Study of the function of the body

Structural Organization of Life

  • Levels of Organization:

    • Chemical Level

      • Atoms

      • Molecules

    • Cellular Level

      • Cells

    • Tissue Level

      • Tissues

    • Organ Level

      • Organs

    • System Level

      • Organ Systems

    • Organismal Level

      • Organism

Chemical Level

  • Atoms: Unique varieties of matter making up substances

    • Common Body Elements: CHNOPS (Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur)

  • Molecules/Compounds: Composed of two or more atoms

    • Most Common Body Molecule: H2O (Water)

    • Common Organic Molecules: Carbohydrates, proteins, lipids, nucleic acids

Cell Structure

  • Cell: Smallest unit of life

    • Organelles: Specialized structures within a cell performing distinct functions

      • Example organelles: Nucleus, mitochondria

Tissue Level

  • Tissues: Groups of cells working together to perform a common function

  • Four Major Tissue Types (CMEN):

    • Connective Tissue: Connects different tissues

    • Muscle Tissue: Contracts to cause movement

    • Epithelial Tissue: Lines cavities and surfaces, covers organs

    • Nervous Tissue: Conducts impulses for communication

Organ Level

  • Organs: Composed of two or more tissue types performing specific functions

    • Examples: Heart, lungs, kidneys, skin, esophagus

Organ Systems

  • Definition: Groups of organs working together to perform vital functions

  • Major Human Body Systems:

    • Integumentary

    • Cardiovascular

    • Skeletal

    • Lymphatic/Immunity

    • Muscular

    • Respiratory

    • Nervous

    • Endocrine

    • Digestive

    • Urinary

    • Reproductive

Integumentary System

  • Functions: Protects deeper tissues, synthesizes vitamin D, houses receptors and glands

Skeletal System

  • Functions: Protects/supports organs, framework for muscle movement, forms blood cells, stores minerals

Muscular System

  • Functions: Manipulation of the environment, locomotion, facial expression, maintains posture, produces heat

Nervous System

  • Functions: Fast-acting control system, responds to changes by activating muscles/glands

Cardiovascular System

  • Functions: Transports blood (oxygen, nutrients, waste), heart pumps blood

Lymphatic System/Immunity

  • Functions: Returns fluid to blood, disposes of debris, houses lymphocytes for immune response

Respiratory System

  • Functions: Maintains oxygen supply, removes carbon dioxide, gas exchange in lungs

Endocrine System

  • Functions: Glands secrete hormones that regulate growth, reproduction, metabolism

Digestive System

  • Functions: Breaks down food, absorbs nutrients, eliminates waste as feces

Urinary System

  • Functions: Eliminates nitrogenous wastes, regulates water and electrolyte balance

Reproductive System

  • Functions: Production of offspring, hormones regulating sex characteristics

Organism Level

  • A collective group of organ systems acting together (individual)

Anatomical Position

  • Standing erect, facing observer, feet flat and forward, arms at sides, palms facing forward

Anatomical Terms

  • Directional Terms:

    • Superior / Inferior: Towards/away from head

    • Anterior (Ventral) / Posterior (Dorsal): Towards front/back of body

    • Medial / Lateral: Towards/Away from midline

    • Proximal / Distal: Closer to/Farther from point of attachment

    • Superficial / Deep: Closer to surface/Away from surface

Regional Terms

  • Includes areas like:

    • Frontal, Thoracic, Orbital, Axillary, Nasal, Sternal, Oral, and others

Body Planes

  • Sagittal: Divides body into right and left sides

  • Frontal: Divides body into anterior and posterior parts

  • Transverse: Divides body into superior and inferior parts

Body Cavities

  • Dorsal Cavity: Cranial (brain), Vertebral (spinal cord)

  • Ventral Cavity: Thoracic (heart, lungs) and Abdominopelvic (digestive organs, reproductive organs)

Ventral Membranes

  • Serous Membranes: Line cavities and secrete fluid reducing friction

    • Parietal serosa: lines cavity wall

    • Visceral serosa: against organs (Includes pericardium, pleura, peritoneum)

Homeostasis

  • Definition: Ability to maintain stable internal conditions despite changes

Major Components of Feedback Systems

  • Stimulus: Change in variable

  • Receptor: Monitors change

  • Control Center: Sets normal range, determines response

  • Effector: Carries out response to restore balance

Types of Feedback Systems

  • Negative Feedback: Reduces stimulus; most common (e.g., blood glucose regulation)

  • Positive Feedback: Enhances stimulus; used in childbirth, urination