NUR 101: Body Structure and Function Module A: The Structure and Function of the Body Terms associated with structure and function of the body Anatomy is the study of the structure of an organism and the relationship of its parts. Physiology is the study of the functions of living organisms and their parts. Organizational levels of the body Cells Tissue Organs Systems Terms associated with structure and function of the body Anatomical position- The body is in an erect or standing posture with the arms at the sides and the palms are forward. The head and feet also point forward. Supine or prone- In the supine position the body is lying face upward and in the prone position the body is lying face down Relationship of anatomical directions to the body Superior Inferior Anterior Posterior Medial Lateral Proximal Distal Superficial Deep Planes or body sections Sagittal Midsagittal Frontal Transverse Ventral Body Cavity Components 1. 2. 1. 2. THORACTIC CAVITY includes: Mediastinum – midportion of thoracic cavity; heart trachea, and blood vessels Pleural cavities – right lung located in the right pleural cavity and the left lung in the left pleural cavity ABDOMINOPELVIC CAVITY includes: Abdominal cavity- Liver, gallbladder ,stomach, spleen, pancreas, small intestine, parts of large intestine Pelvic cavity- lower colon (sigmoid), rectum, urinary bladder, reproductive organs Dorsal Body Cavity Components 1. CRANIAL CAVITY includes: The space inside the skull which contains the brain 2. SPINAL CAVITY includes: The space inside the spinal column which contains the spinal cord ABDOMINOPELVIC REGIONS 1. 2. 3. Upper abdominopelvic regions : right and left hypochondriac region, and the epigastric region lie above an imaginary line across the abdomen at the level of the ninth rib cartilages Middle regions: right and left lumbar region, and the umbilical region lie below an imaginary line across the abdomen at the level of the top of the hip bones. Lower regions: right and left iliac regions and the hypogastric region lie below an imaginary line across the abdomen at the level of the top of the hip bones BODY REGIONS AXIAL- The axial portion of the body consists of the head, neck and torso or trunk. APPENDICULAR- The appendicular portion consists of the upper and lower extremities. Balance of Body Functions 1. HOMEOSTASIS-is the relative constancy of the internal environment. The activity of the cells and external disturbances threaten internal stability (homeostasis) ,the body must work to maintain or restore stability. To accomplish self-regulation, a highly complex and integrated communication control system is utilized. The control system is called a feedback loop. Balance of Body Functions FEEDBACK LOOPS : a highly complex and integrated communication control network, classified as negative or positive; negative feedback loops are the most important and numerous homeostatic control mechanisms.