Vocabulary and Introduction

Anatomy and Physiology

Anatomy is the study of the structure and organization of the human body. Physiology is the study of the function of the body and its parts.

• Anatomy: Focuses on body parts, their locations, and relationships.

• Physiology: Explores how body parts work and interact to maintain life.

Levels of Organization

Hierarchical Structure of the Human Body

• Chemical Level: Atoms, molecules, macromolecules, organelles

• Cellular Level: Cells are made up of molecules

• Tissue Level: Made up of similar cells

• Organ Level: Composed of several types of tissues

• Organ System Level: Organs with coordinated functions

• Organism Level: An individual living being formed from combined organ systems

Organ Systems of the Human Body

Overview and Functions

• Integumentary System

  • Organs: Skin, nails, associated glands

  • Functions: Protects underlying tissues, regulates body temperature

• Skeletal System

  • Organs: Bones, ligaments, cartilages

  • Functions: Supports the body, protects vital organs, stores minerals, site of blood cell production

• Muscular System

  • Organs: Skeletal muscles, tendons

  • Functions: Moves the body and body parts, produces heat

• Respiratory System

  • Organs: Nose, pharynx, larynx, trachea, bronchi, lungs

  • Functions: Exchanges O2 and CO2 between air and blood, regulates pH, sound production

• Cardiovascular System

  • Organs: Blood, heart, arteries, veins, capillaries

  • Functions: Transports heat and materials to and from body cells

• Lymphoid System

  • Organs: Lymph, lymphatic vessels, lymphoid organs and tissues

  • Functions: Collects and cleanses interstitial fluid, returns it to blood, provides immunity

• Urinary System

  • Organs: Kidneys, ureters, urinary bladder, urethra

  • Functions: Removes wastes, regulates water and electrolyte balance, excretes urine

• Endocrine System

  • Organs: Hormone-producing glands (pituitary, thyroid, etc.)

  • Functions: Secretes hormones that regulate body functions

• Nervous System

  • Organs: Brain, spinal cord, nerves, sensory receptors

  • Functions: Rapidly coordinates body functions, enables learning and memory

• Digestive System

  • Organs: Mouth, pharynx, esophagus, stomach, intestines, liver, pancreas, gallbladder

  • Functions: Digests food, absorbs nutrients

• Male Reproductive System

  • Organs: Testes, epididymides, vas deferentia, prostate, bulbourethral glands, seminal vesicles, penis

  • Functions: Produces sperm, transmits them into the female vagina during sexual intercourse

• Female Reproductive System

  • Organs: Ovaries, uterine tubes, uterus, vagina, vulva

  • Functions: Produces oocytes, receives sperm, provides intrauterine development of offspring, enables birth of an infant

Directional Terms

Describing Locations in the Body

Directional terms are used to convey the location of one body part in relation to another.

• Anterior (ventral): Toward the front of the body

  • Example: The abdomen is anterior to the back

• Posterior (dorsal): Toward the back of the body

  • Example: The spine is posterior to the breast bone

• Superior (cephalic): Toward the top/head

  • Example: The nose is superior to the mouth

• Inferior (caudal): Away from the top/head

  • Example: The navel is inferior to the nipples

• Medial: Toward the midline of the body

  • Example: The breastbone is medial to the nipples

• Lateral: Away from the midline of the body

  • Example: The ears are lateral to the cheeks

• Visceral: Pertaining to internal organs

  • Example: The visceral pleura covers the lung

• Parietal: Pertaining to the wall of a body cavity

  • Example: The parietal pleura lines the pleural cavity

• Superficial (external): Toward or on the body surface

  • Example: The skin is superficial to the muscles

• Deep (internal): Away from the body surface

  • Example: The intestines are deep to the abdominal muscles

• Proximal: Closer to the beginning

  • Example: The elbow is proximal to the wrist

• Distal: Farther from the beginning

  • Example: The hand is distal to the wrist

• Central: At or near the center of the body or organ

  • Example: The central nervous system is in the middle of the body

• Peripheral: External to or away from the center

  • Example: The peripheral nervous system extends away from the central nervous system

Body Regions

Axial and Appendicular Divisions

• Axial: Head, neck, trunk

• Appendicular: Arms, legs, girdles

Major Regions of the Axial Portion

• Head and Neck: Auricular, buccal, cephalic, cervical, cranial, facial, nasal, oral, orbital, otic

• Anterior Trunk: Abdominal, inguinal, pectoral, presternal, pubic, sternal

• Posterior Trunk: Dorsum, gluteal, lumbar, sacral, scapular, vertebral

• Lateral Trunk: Axillary, coxal

• Inferior Trunk: Genital, perineal

Major Regions of the Appendicular Portion

• Upper Limb: Antebrachial, brachial, carpal, cubital, deltoid, digital, palmar

• Lower Limb: Crural, digital, femoral, patellar, pedal, plantar, popliteal, sural, tarsal

Body Planes and Sections

Dividing the Body for Study

1. Transverse (horizontal) plane: Divides the body into superior and inferior sections

2. Sagittal plane: Divides the body into right and left portions

   • A median plane passes through the midline; paramedian does not pass through midline

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

4. Longitudinal and cross-sectional axes: Cuts made through sagittal and frontal planes, parallel to the longitudinal axis of the body

5. Oblique sections: Cuts made at angles between the longitudinal and cross-sectional axes

Note: The planes that are longitudinal are the frontal plane and paramedian plane.

Body Cavities

Major Body Cavities and Their Contents

• Cranial cavity: Enclosed in the bones of the skull, contains the brain

• Vertebral canal: Contains the spinal cord

• Thoracic cavity: Protected by the thoracic cage, contains the heart and lungs

  • Subdivisions: pleural cavities (lungs), pericardial cavity (heart), mediastinum

• Abdominopelvic cavity:

  • Abdominal cavity: Contains stomach, intestines, liver, gallbladder, pancreas, spleen, kidneys

  • Pelvic cavity: Contains urinary bladder, sigmoid colon, rectum, internal reproductive organs

Serous Membranes

Structure and Function

• Organs within the thoracic and abdominal cavities are surrounded by tissue known as serous membranes.

• Serous membranes have an outer layer (parietal membrane) and an inner layer (visceral membrane).

• Types of serous membranes:

  • Pleura: Around the lungs

  • Pericardium: Around the heart

  • Peritoneum: Around the abdominal organs

• The parietal peritoneum lines the walls of the abdominal cavity, but not the pelvic cavity.

• The visceral peritoneum covers the surface of abdominal organs.

• Some organs (kidneys, pancreas, parts of intestines) are located behind the parietal peritoneum in the retroperitoneal space.

Abdominopelvic Subdivisions

Quadrants and Regions

• Four Quadrants:

  • Right upper

  • Right lower

  • Left upper

  • Left lower

• Nine Regions:

  • Epigastric

  • Right flank

  • Left flank

  • Right hypochondriac

  • Left hypochondriac

  • Umbilical

  • Left iliac

  • Right iliac

  • Right inguinal

Examples of Organ Locations by Quadrant

• Right upper quadrant: gallbladder, kidney, ascending and transverse colon

• Right lower quadrant: appendix, part of the urinary bladder, part of the rectum

• Left upper quadrant: stomach, spleen, kidney

• Left lower quadrant: parts of the urinary bladder, part of the rectum, descending and sigmoid colon

Summary Table: Directional Terms

Summary Table: Body Cavities

Additional info:

• These notes provide foundational terminology and organization for further study in Anatomy & Physiology, including clinical applications such as medical imaging, surgery, and diagnosis.

• Understanding body planes and regions is essential for describing locations of injuries, diseases, and procedures.