The Human Body Chapter 1
Human Anatomy and Physiology Anatomy: The study of body structures and their relationships Static within a species Physiology: The study of the functions of body structures Dynamic within a species
Subdivision Examples Anatomy Physiology Gross anatomy Regional Systemic Surface Microscopic anatomy Cytology Histology Embryology Developmental anatomy Others Neurophysiology Pathophysiology Cardiovascular physiology Renal Physiology Others
Life is an Emergent Property Atoms Molecules Organelles Cells Tissues Organs Organ systems Listed in fig 1.3 Organismal level
Organ Systems ORGAN SYSTEM COMPONENTS FUNCTIONS Integumentary Skin, hair, nails Protection Skeletal Bones Support/movement Nervous Brain, spinal cord, nerves, sense organs Control and communication Muscular Muscles Movement Endocrine Hormones and associated glands Homeostasis Cardiovascular Heart, blood vessels, blood Transport of substances Lymphatic Lymph vessels and lymph nodes Transport, immunity Respiratory Nose, trachea, lungs Transport of gases Digestive Mouth, esophagus, stomach, intestines Energy acquisition and food processing Urinary Kidneys, ureters, bladder, urethra Water balance Reproduction Gonads Propagation
Life’s Essentials Maintain boundaries Move Respond to environment Digestion Excretion Metabolism Reproduce Grow
Survival Essentials Nutrients Oxygen Water Normal body temperature Fuel for the cells Building materials Oxygen Release energy from nutrients Water Facilitates reactions and excretions/secretions Normal body temperature Regulate metabolic reactions Atmospheric pressure Corresponds with gas exchange w/i cells Adequate amounts, not just presence maintains a healthy state
Homeostasis Dynamic state of equilibrium 3 components Receptor (afferent) Control center (set point) Effector (efferent) Imbalance causes illness & disease Increase with age Disruptions in feedback
Feedback Negative Positive Most homeostatic mechanisms Turn off or slow original stimuli Stabilizes Body temperature, heart and breathing rate, & blood glucose Positive Increases the original stimuli Oxytocin (labor) and blood clotting
Anatomical Language
Anatomical Position Standing tall with upper limbs at sides and face, palms and toes forward Reference position when describing body part locations Left and right is specimen’s Variations for bipeds and quadrupeds
Anatomical Regions to Know
Anatomical Directions to Know Superior/ inferior Cranial/caudal Ventral/ dorsal Anterior/ posterior Medial/ lateral Intermediate/ proximal/ distal Superficial/ deep External/ internal Supine/ prone Ipsilateral/ contralateral Study tip: pick two structures on self and describe as many ways as possible
Body Planes are Like Breads Frontal (coronal) section: divides anterior and posterior e.g.: loaf of bread Sagittal section: divides the body longitudinally into left and right Midsagittal: equal parts Parasagittal: off midline e.g.: hotdog bun Transverse (cross) section: divides superior and inferior e.g.: hamburger bun or bagel Oblique section: diagonal cuts
Body Cavities Dorsal Ventral Cranial: brain Vertebral: spinal cord Thoracic Left & right pleura Mediastinum (pericardial) Abdominopelvic No real separation Protection differences Diaphragm divides
Serous Membranes Double-layer membrane separated by serous fluid Reduces friction; lubricates Line walls and organs of ventral body cavities Parietal serosa lines walls Visceral serosa lines organs (viscera) Named for associated organs Never exposed to external environment
Other Body Cavities Open to environment (generally)
Abdominopelvic Subdivisions Regions (9) Quadrants (4) Epigastric Umbilical Hypogastric Hypochondriac Lumbar Inguinal Anatomists use; references location and orientation of internal organs Clinicians use; references to describe pain, tenderness, and injuries