Anatomy and Physiology

Overview of Anatomy and Physiology

  • Anatomy: Describes the structures of the body including:

    • What they are made of

    • Where they are located

    • Associated structures

  • Physiology: Study of:

    • Functions of anatomical structures

    • Individual and cooperative functions

Types of Anatomy

  • Human anatomy: Divided into subcategories:

    • Gross (Macroscopic) Anatomy: Examines large, visible structures:

    • Surface anatomy: exterior features

    • Regional anatomy: body areas

    • Sectional anatomy: cross-sections

    • Systemic anatomy: organ systems

    • Clinical anatomy: medical specialties

    • Developmental anatomy: from conception to adulthood (includes embryology)

  • Microscopic anatomy: Examines cells and molecules:

    • Cytology: study of cells

    • Histology: study of tissues

Human Physiology

  • Cell physiology: Functions of cells

  • Organ physiology: Functions of specific organs

  • Systemic physiology: Functions of organ systems

  • Pathological physiology: Effects of diseases on organs or systems

Levels of Organization

  • Chemical level:

    • Atoms are the smallest stable units of matter

    • Molecules consist of groups of atoms

  • Cellular level:

    • Cells are the smallest living units in the body

  • Tissue level:

    • A tissue is a group of cells working together

  • Organ level:

    • Organs are made of two or more tissues working together

  • Organ system level:

    • An organ system is a group of interacting organs (humans have 11 organ systems)

  • Organism level:

    • An individual life form is considered an organism

Organ Systems and Their Functions

  • Integumentary System:

    • Major Organs: Skin, hair, sweat glands, nails

    • Functions: Protects against environmental hazards, regulates body temperature, provides sensory information

  • Skeletal System:

    • Major Organs: Bones, cartilages, associated ligaments, bone marrow

    • Functions: Provides support/protection for tissues, stores calcium, forms blood cells

  • Muscular System:

    • Major Organs: Skeletal muscles and associated tendons

    • Functions: Provides movement, protection/support for tissues, generates heat to maintain body temperature

  • Nervous System:

    • Major Organs: Brain, spinal cord, peripheral nerves, sense organs

    • Functions: Direct responses to stimuli, coordinates activities of organ systems, interprets sensory information about external conditions

  • Endocrine System:

    • Major Organs: Pituitary gland, thyroid gland, pancreas, adrenal glands, gonads, endocrine tissues

    • Functions: Directs long-term changes in activities of organ systems, adjusts metabolic activity and energy use by the body, controls changes during development

  • Cardiovascular System:

    • Major Organs: Heart, blood, blood vessels

    • Functions: Distributes blood, water, dissolved materials (including nutrients, waste products, oxygen, carbon dioxide);
      distributes heat, assists in control of body temperature

  • Lymphatic System:

    • Major Organs: Spleen, thymus, lymphatic vessels, lymph nodes, tonsils

    • Functions: Defends against infection and disease, returns tissue fluids to bloodstream

  • Respiratory System:

    • Major Organs: Nasal cavities, larynx, trachea, bronchi, lungs (alveoli)

    • Functions: Delivers air to alveoli, provides oxygen to bloodstream, removes carbon dioxide from bloodstream, produces sounds for communication

  • Digestive System:

    • Major Organs: Teeth, tongue, pharynx, esophagus, stomach, small intestine, large intestine, liver, gallbladder, pancreas

    • Functions: Processes/digests food, absorbs/conserves water, absorbs nutrients, stores energy reserves

  • Urinary System:

    • Major Organs: Kidneys, ureters, urinary bladder, urethra

    • Functions: Excretes waste products from blood, regulates water balance, stores urine prior to elimination, regulates blood ion concentrations and pH

  • Male Reproductive System:

    • Major Organs: Testes, epididymides, ductus deferentia, seminal vesicles, prostate gland, penis, scrotum

    • Functions: Produces male sex cells (sperm), seminal fluids, hormones; sexual intercourse

  • Female Reproductive System:

    • Major Organs: Ovaries, uterine tubes, uterus, vagina, labia, clitoris, mammary glands

    • Functions: Produces female sex cells (oocytes) and hormones; supports developing embryo from conception to delivery; provides milk to nourish newborn; sexual intercourse

Medical Terminology

  • Medical terminology: Related terms concerning the body in health and disease

  • Involves using word roots, prefixes, suffixes, and combining forms to build terms

  • Understanding word parts aids comprehension of anatomy and physiology

  • Surface anatomy: Primarily deals with locating structures on or near body surface

Anatomical Terminology

  • Anatomical position: Hands at sides, palms forward (standard reference for descriptions)

    • Anterior view: Body viewed from the front

    • Posterior view: Body viewed from the back

    • Supine: Lying down, face up

    • Prone: Lying down, face down

Anatomical Landmarks

  • Anatomical landmarks: Specific terms corresponding to surfaces:

    • Frontal (forehead)

    • Nasal (nose)

    • Ocular, orbital (eye)

    • Cranial (skull)

    • Facial (face)

    • Otic (ear)

    • Buccal (cheek)

    • Cervical (neck)

    • Thoracic (chest)

    • Abdominal (abdomen)

    • Umbilical (navel)

    • Mental (chin)

    • Axillary (armpit)

    • Brachial (arm)

    • Antecubital (front of elbow)

    • Antebrachial (forearm)

    • Carpal (wrist)

    • Palmar (palm)

    • Pelvic (pelvis)

    • Manual (hand)

    • Digits (fingers)

    • Inguinal (groin)

    • Pubic (pubis)

    • Femoral (thigh)

    • Patellar (kneecap)

    • Crural (leg)

    • Tarsal (ankle)

    • Hallux (great toe)

    • Pedal (foot)

Anatomical Regions and Directions

  • Abdominopelvic quadrants:

    • Right Upper Quadrant (RUQ)

    • Right Lower Quadrant (RLQ)

    • Left Upper Quadrant (LUQ)

    • Left Lower Quadrant (LLQ)

  • Abdominopelvic regions:

    • Right hypochondriac, epigastric, umbilical, hypogastric (pubic), left hypochondriac, right lumbar, left lumbar, right inguinal, left inguinal

  • Directional references:

    • Superior: Above; at a higher level (e.g., head)

    • Inferior: Below; at a lower level (e.g., feet)

    • Anterior: Front surface (ventral)

    • Posterior: Back surface (dorsal)

    • Lateral: Away from midline

    • Medial: Toward midline

    • Proximal: Near the point of attachment of a limb to the trunk

    • Distal: Away from the point of attachment

    • Superficial: Near the surface

    • Deep: Further from the surface

    • Caudal: Toward the tail (coccyx)

Sectional Anatomy

  • Sectional anatomy: Involves slicing through a three-dimensional structure:

    • Planes:

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

    • Sagittal plane: Divides body into left and right portions.

      • Midsagittal plane: Located in the midline

      • Parasagittal plane: Offset from the middle

    • Transverse (horizontal) plane: Divides body into superior and inferior portions

Body Cavities

  • Body cavities: Closed, fluid-filled cavities lined with serous membranes, housing vital organs.

  • Functions:

    1. Protect delicate organs from shocks/impacts.

    2. Permit changes in size/shape of internal organs.

  • Serous membranes: Consist of parietal (lines cavity) and visceral (covers organs) layers, with serous fluid that lubricates and reduces friction.

  • Ventral body cavity: Divided by the diaphragm into the thoracic and abdominopelvic cavities:

    • Thoracic cavity: Contains lungs (pleural cavities) and heart (pericardial cavity).

    • Abdominopelvic cavity: Contains abdominal organs and pelvic organs, including the peritoneal cavity.

Support Structures

  • Supporting connective tissues: Include cartilage and bone.

  • Cartilage: Provides support and shock absorption with matrix containing polysaccharides; notable types include hyaline, elastic, and fibrocartilage.

  • Bone (osseous tissue): Provides structural support, mineral storage and protective factors; structured with osteocytes situated in lacunae.

Tissue Repair and Aging

  • Regeneration ability varies among tissues: Epithelia and connective tissues regenerate well, whereas skeletal, cardiac, and nervous tissues regenerate poorly, often replaced by fibrous tissue.

  • Aging effects: Aging leads to slower regeneration and structural changes such as thinner epithelia and fragile connective tissue. Cancer rates increase with age, influenced by environmental factors.