Module 1: The Body PDF

Concepts in Anatomy & Physiology MPAS 5003 The Body Overview of Content § Introduction to anatomy § Gross anatomy and histology § Radio imaging § Planes of symmetry § Body cavities and membranes The Basics Anatomy – study of the structural basis of body function Physiology –...

Concepts in Anatomy & Physiology MPAS 5003 The Body Overview of Content § Introduction to anatomy § Gross anatomy and histology § Radio imaging § Planes of symmetry § Body cavities and membranes The Basics Anatomy – study of the structural basis of body function Physiology – study of the functional relevance of a structure § Functional morphology – the relationship between structure and function All the above dictate homeostasis and disruptions result in disease (i.e., pathology) Requirements for Survival Water – most abundant and makes up most cells, provides the environment needed for chemical reactions Homeostatic balance of body temperature Atmospheric pressure – i.e., concentration of gases to allow for gas exchange with the lungs (air is ~80% nitrogen) Appropriate physiologic pH Nutrients: chemicals for energy and building of cells Examples: carbohydrates, proteins, fats, minerals, and vitamins Electrolytes: sodium, potassium, calcium, phosphate, and magnesium Homeostasis Maintenance of relatively stable internal conditions despite environmental changes which is maintained by the contribution of all organ systems. Examples: Body temperature/sweating/erector pilli muscles Blood pH/heart rate/respiratory rate Anatomy Gross Anatomy § Surface anatomy; e.g. dissection § Radiological anatomy; e.g. non- invasive imaging § Systemic anatomy; e.g. cardio- vascular § Regional anatomy; e.g. abdomino- pelvic § Developmental anatomy; e.g. ‘Carnegie’ stages Histology (microscopic anatomy) § Microscopic analysis of diseased tissue; e,g, dermatological lesions Human Structure Not all people have “normal” position of organs Terminology § Situs solitus – normal arrangement § Situs inversus – reversed position of organs. § e.g. Transposition of the great vessels of the heart § Situs perversus – one organ atypically positioned Organ Systems § Integumentary § Lymphatic § Skeletal § Respiratory § Muscular § Digestive § Nervous § Urinary § Endocrine § Male reproductive § Circulatory § Female reproductive Anatomical Position Standard Anatomical Position = erect with feet flat & slightly angled outward; arms straight and palms forward Important to note anatomical planes of orientation § Frontal plane: front/back § Sagittal plane: side/side § Transverse plane: top/bottom Directional Terms Directional Terms Directional Terms Other Directional Terms Other Directional Terms Body Regions Axial region § Head § Neck (cervical region) § Trunk § Thoracic region § Abdominal region § Four quadrants [lines that cross the umbilicus – often used in clinical setting] § Nine regions § Midclavicular line, subcostal line, intertubercular line Body Regions Body Regions Appendicular region § Upper limbs § Arm (brachial) e.g. brachial artery § Forearm (antebrachial) § Wrist (carpal) § Hand (manus) § Fingers (digits) § Lower limbs § Thigh (femoral) § Leg (crural) § Ankle (tarsal) § Foot (pedal) Body Cavities and Membranes Four major body cavities plus several smaller cavities 1. Cranial 2. Vertebral 3. Thoracic 4. Abdominopelvic Cavities are lined with epithelial membranes and contain fluid Body Cavities and Membranes 1. Cranial Cavity § Enclosed by cranium 2. Vertebral canal § Enclosed by vertebral column Both lined by meninges (dura mater) Body Cavities and Membranes 3. Thoracic Cavity § Divided into several smaller cavities § Pleural cavity (contains lungs with visceral and parietal pleura) § Mediastinum § Pericardial cavity § Contains the heart § Visceral and parietal pericardium § Pericardial fluid Body Cavities and Membranes 4. Abdominopelvic cavity § Abdominal cavity § Superior portion § Contains most of the digestive organs § Spleen, kidneys, and proximal ureters § Pelvic cavity § Inferior portion § Distal large intestine, urinary bladder, urethra, and reproductive organs § Here we have the visceral and parietal peritoneum Body Cavities and Membranes Smaller Cavities § Oral cavity § Nasal cavity § Middle ear cavity § Orbital cavity § Synovial cavities Anatomical Terms of Movement Anatomical Terms of Movement Anatomical Terms of Movement Imaging Often Used in Medicine X-rays Ultrasound CT scan Magnetic Resonance Imaging Positron emission testing (PET) Scan Homeostasis Maintenance of relatively stable internal conditions despite continuous changes in environment § A dynamic state of equilibrium, always readjusting as needed § Maintained by contributions of all organ systems Homeostasis Body must be constantly monitored and regulated to maintain homeostasis § Nervous and endocrine systems, as well as other systems, play a major role in maintaining homeostasis Homeostasis Homeostatic control of variables involves three components: 1. Receptor (sensor) § Monitors environment § Responds to stimuli (things that cause changes in controlled variables) 2. Control center § Determines set point at which variable is maintained § Receives input from receptor § Determines appropriate response (increase or decrease) 3. Factors that can change include (effectors): blood sugar, body temperature, blood volume (pressure), hormone levels, ion content, metabolic rate, etc. Homeostasis Negative feedback § Regulation of body temperature (a nervous system mechanism) sweating vs shivering § Regulation of blood glucose by insulin and glucagon (an endocrine system mechanism) cellular uptake Homeostasis Positive feedback § Response enhances or exaggerates the original stimulus § May exhibit a cascade or amplifying effect as feedback causes variable to continue in same direction as initial change § Usually controls infrequent events that do not require continuous adjustment, for example: § Enhancement of labor contractions by oxytocin § Platelet plug formation and blood clotting Homeostasis Life is good once you achieve homeostasis!  Concepts in Anatomy & Physiology Questions: [email protected] MPAS 5003 Chemistry and Biochemistry