Anatomy Chapter 1

The study of the form and function of anatomical structures.

• Anatomy: study of the structural bases of body function

• Physiology: study of the functional relevance of a structure

• Functional morphology (3F’s) “Form Follows Function”

Compare the different ways to study anatomy

• Gross Anatomy: the study of internal and external body features through seeing them with a naked eye (dissection)

• Microscopic Anatomy (Histology): studying the smallest structures of the body such as tissues, cells, and molecules (using microscopes)

• Radiologic Anatomy: study of anatomy using x-rays

• Systemic vs. Regional Anatomy

  • Systemic: based on certain body systems (ex: skeletal system (all the bones in the body))

  • Regional: overall anatomy of a specific region (ex: all the bones, neurons, blood vessels in the arm region)

Human variations

• Situs solitus - normal arrangement

• Situs invertus - reversed position of organs

• Situs perversus - one organ atypically positioned

Structural levels of an organism

• Atoms

• Molecules/Macromolecules

• Organelles

• Cells - smallest “living” unit

• Tissues

• Organs

• Organ systems

• Organism - single, complete individual

The eleven (11) organ systems of the human body.

• 1. Integumentary 

  • Organs: skin, hair, nails, cutaneous glands

  • Functions: protection, water regulation, thermoregulation, vitamin D synthesis, cutaneous sensation, non-verbal communication 

• 2. Skeletal 

  • Organs: bones, cartilage, ligaments

  • Functions: support, movement, protective enclosure of the viscera, blood formation, mineral storage, electrolyte and acid-base balance

• 3. Muscular 

  • Organs: skeletal muscles

  • Functions: movement, stability, communication, control of body openings, heat production

• 4. Nervous 

  • Organs: brain, spinal cord, nerves, ganglia

  • Functions: rapid internal communication, coordination, motor control, sensation

• 5. Endocrine 

  • Organs: pituitary gland, pineal gland, thyroid gland, parathyroid gland, thymus, adrenal glands, pancreas, testes, ovaries

  • Functions: hormone production, internal chemical communication and coordination

• 6. Circulatory 

  • Organs: heart, blood vessels

  • Functions: distribution of nutrients, oxygen, wastes, hormones, electrolytes, heat, immune cells, and antibodies; fluid, electrolyte, and acid-base balance

• 7. Lymphatic 

  • Organs: lymph nodes, lymphatic vessels, thymus, spleen, tonsils

  • Functions: recovery of excess tissue fluid, detection of pathogens, production of immune cells, defense against disease

• 8. Respiratory 

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

  • Functions: absorption of oxygen, discharge of carbon dioxide, acid-base balance, speech

• 9. Digestive 

  • Organs: teeth, tongue, salivary glands, esophagus, stomach, small and large intestines, liver, gallbladder, pancreas

  • Functions: nutrient breakdown and absorption; liver functions include metabolism of carbohydrates, lipids, proteins, vitamins, and minerals; synthesis of plasma protein; disposal of drugs, toxins, and hormones; and cleansing of blood

• 10. Urinary 

  • Organs: kidneys, ureters, urinary bladder, urethra

  • Functions: elimination of wastes; regulation of blood volume and pressure; stimulation of red blood cell formation; control of fluid, electrolyte, and acid-base balance; detoxification

• 11. Reproductive

  • Male 

    • Organs: testes, epididymides, spermatic ducts, seminal vesciles, prostate gland, bulbourethral glands, penis

    • Functions: production and delivery of sperm; secretion of sex hormones

  • Female

    • Organs: ovaries, uterine tubes, uterus, vagina, mammary glands

    • Functions: production of eggs, site of fertilization and fetal development, fetal nourishment, birth, lactation, secretion of sex hormones

Anatomical positions

• Standing erect with feet flat, ankles together

• Arms at the sides (supinated)

• Palms, face, and eyes facing forward

• Provides a constant reference of body position

• Note your reference vantage point for identifying left and right structures (identify from the perspective of the person not your pov ex: their right not your right)

Anatomical planes

• Prone - lying down on stomach

• Supine - lying down on back

• Sagittal plane - divides right/left portions

• Median (midsagittal) plane - equal halves

• Parasagittal - unequal right/left halves

• Front (coronal) plane - divides anterior (toward the front of the body) and posterior (toward the back of the body) portions*

• Transverse plane - divides superior (above/up) and inferior (below/down) portions*

Directional terms

• Medial vs Lateral

  • Medial - inward or towards the midline of the body

  • Lateral - outward or away from the midline of the body

• Proximal vs Distal

  • Proximal - closer to the trunk 

  • Distal - farther away from the trunk 

• Ventral vs Dorsal

  • Ventral - toward the anterior part of our body

  • Dorsal - toward the posterior part of our body

• Superficial vs Deep

  • Superficial - closer to the body surface 

  • Deep - farther/deeper into the body surface 

Axial vs. Appendicular regions

• Axial Region of the Body

  • Head

  • Neck (cervical region)

  • Trunk

  • Thoracic Region

  • Lungs, heart, mediastinum

  • Abdominal Region

  • 4 quadrants

  • 9 regions

• Appendicular Region of the Body

  • Shoulder Girdle & Upper limbs

  • Scapula

  • Clavicle 

  • Arm (brachial region)

  • Forearm (antebrachial region)

  • Wrist (carpal region)

  • Hand (manual region)

  • Fingers (digits)

  • Pelvic Girdle & Lower Limbs

  • Pelvic Bones: ileum, ischium, pubis

  • Thigh (femoral region)

  • Leg (crural region)

  • Ankle (tarsal region)

  • Foot (pedal region)

  • Toes (digits)

Body cavities, regions, and membranes

• Cranial cavity 

  • Enclosed by cranium (braincase)

  • Contains brain

• Vertebral canal

  • Enclosed by vertebral column (backbone)

  • Contains spinal cord

• Thoracic cavity

  • Superior to the diaphragm

  • Mediastinum

  • Pericardium

• Pericardial cavity

  • Pericardial fluid

  • Pleura

• Pleural cavity

  • Pleural fluid

• Abdominopelvic cavity

  • Abdominal cavity

    • Superior portion

    • Contains most of the digestive organs

    • Spleen, kidneys, and ureters

  • Pelvic cavity

    • Inferior position

    • Distal large intestine, urinary bladder, urethra, and reproductive organs

• Inferior cavity

  • Visceral (inner lining)

  • Parietal (outer lining)

• Serous Membranes of the Abdominal Cavity

  • Peritoneum

  • Parietal and visceral

  • Peritoneal cavity

  • Peritoneal fluid

  • Retroperitoneal position - outside of peritoneum

  • Intraperitoneal - surrounded by peritoneum

  • Serosa - visceral peritoneum divides and wraps around organs