CH 01 ORIENTATION TO THE STUDY OF THE HUMAN BODY This chapter provides a review of concepts and terms inherent in the study of Anatomy and Physiology. These concepts and terms include, but are not limited to: THREE ESSENTIAL CONCEPTS STRESSED IN ANATOMY The complementarity of structure and function. The hierarchy of structural organization. The importance of homeostasis. BASIC DEFINITIONS 1 - ANATOMY Anatomy is the structural study of body parts and the relationships among them. Areas of anatomical specialization include: Macroscopic (Gross) Regional Systemic Surface Microscopic Cytology Histology Developmental Varying Specializations Embryology Pathological anatomy Radiographic anatomy Molecular anatomy 2 - PHYSIOLOGY Physiology studies the methods of operation of body structures. Three major organ/system subdivisions include renal, neurophysiological, and cardiovascular. 1
HIERARCHY OF STRUCTURAL ORGANIZATION Starting from the smallest to the largest: Chemical Level Cellular Level Tissue Level Organ Level Organ/System Level Organism HUMAN BODY SYSTEMS There are eleven or twelve human body systems, depending on whether or not you link or separate the lymphatic and immune systems. Integumentary Skeletal Muscular Nervous Cardiovascular Lymphatic/Immune Endocrine Respiratory Digestive Urinary Reproductive 2
HOMEOSTASIS All parts of the body must constantly communicate with one another in order to maintain harmony among all physical structures and their chemical operations. They must maintain their boundaries as well as a balance of all internal operations. Disruption of homeostasis leads to disease states. MAINTAINING LIFE Staying alive and well involves constantly making metabolic adjustments in response to changing internal and external environmental factors. The key to maintaining homeostasis is metabolism! The process of metabolism provides us with (1) carbon skeletons and (2) recharging of ATP and other TP molecules. The core reaction of metabolism is the process of cellular respiration, which includes glycolysis, TCA/Krebs/Citric Acid cycle, and the electron transport system. Metabolism includes two categories of reactions: Anabolism (Anabolic) Catabolism (Catabolic) Metabolic reactions provide resources for: 1 Movement (irritability, contractility) 2 Digestion 3 Excretion 4 Growth and Differentiation 5 Reproduction SURVIVAL NEEDS Nutrients (inorganic and organic) Oxygen Ambient Temperature Range 3
CONTROL MECHANISMS TO HELP MAINTAIN HOMEOSTASIS Homeostasis is maintained via the interaction of nervous system (NS) and endocrine systems. Three interdependent components are: Receptors Afferent Pathway Control Center Efferent Pathway Effectors FEEDBACK MECHANISMS help enhance operations and/or responses of the NS and endocrine systems. Two forms of feedback systems are Positive Feedback Negative Feedback LANGUAGE OF ANATOMY 1 - CORRECT ANATOMICAL POSITION Body erect, feet together, arms hanging at your sides, palms facing forward, and thumbs pointing away from the body. Remember: right and left refer to the sides of the cadaver - not to your sides! 2 - DIRECTIONAL TERMS Superior (Cranial) Inferior (Caudal) Anterior (Ventral) Posterior (Dorsal) Medial Lateral Intermediate 4
Proximal Distal Superficial Deep 3 - BODY PLANES AND SECTIONS Median (Midsagittal) Plane Parasagittal Plane Frontal (Coronal) Plane Transverse Plane Oblique Plane 4 - BODY CAVITIES Dorsal Cavities Cranial Vertebral Ventral Cavities* Thoracic Abdominopelvic *A band of muscle called the diaphragm, which also assists in respiration, separates the two ventral cavities. 5 - REGIONAL TERMS General Axial Appendicular Head Cephalic Otic 5
Occipital Nasal Frontal Orbital Buccal Mental Neck Shoulder Cervical Scapular Axillary Sternal Acromial Deltoid Chest Thoracic Mammary Arm Brachial Antebrachial Antecubital Oleocranal Hand Manus Palmar Carpal Pollex Digital Abdominal Pelvic Umbilical Inguinal 6
Gluteal Coxal Pubic Perineal Leg Femoral Patellar Crural Peroneal Popliteal Sural Foot Pedal Tarsal Digital Hallux Calcaneal Plantar Spinal Cervical Thoracic Lumbar Sacral 6 - MEMBRANES (SEROSA) OF THE VENTRAL CAVITY Serous membranes are lubricated by serous fluid, which they produce. They are named (in part) for the structure(s) they specifically cover or line. Parietal Visceral 7
7 - QUADRANTS There are four quadrants: Right upper (RUQ), left upper (LUQ), right lower (RLQ), and left lower quadrants (LLQ). 8 - THE ABDOMINO-PELVIC REGIONS Right Hypochondriac Epigastric Left Hypochondriac Right Lumbar Umbilical Left Lumbar Right Iliac (Inguinal) Hypogastric (Pubic) Left Iliac (Inguinal) 8