Unit 1 Unit Of Life And Organization Of Body Structure part I.pptm

Unit Of Life And Organization Of Body Structure By: Dr. Mohd Fauze bin Mahad Jais School of Medicine Learning Outcomes Define anatomy and physiology. Describe the structural organization of the human body. Define the body systems and explain how they relate to one another. Define homeos...

Unit Of Life And Organization Of Body Structure By: Dr. Mohd Fauze bin Mahad Jais School of Medicine Learning Outcomes Define anatomy and physiology. Describe the structural organization of the human body. Define the body systems and explain how they relate to one another. Define homeostasis and explain its importance. Describe the components of a feedback system. Compare the operation of negative and positive feedback systems. Distinguish between symptoms and signs of a disease. Learning Outcomes Describe the anatomical position. Identify the major regions of the body and relate the common names to the corresponding anatomical terms for various parts of the body. Define the directional terms and the anatomical planes and sections used to locate parts of the human body. Describe the principal body cavities and the organs they contain. Explain why the abdominopelvic cavity is divided into regions and quadrants. Definitions Anatomy: science that studies structure Physiology: science that studies body functions Anatomy (structure) determines physiology (functions) Levels of Organization Chemical: atoms molecules Cellular: cells containing organelles Basic unit of life Tissue: groups of cells and surrounding material 4 basic types: epithelial, connective, muscular, nervous Organ: group of tissues performing a common function System: group of organs with a common function Organism: contains all systems of an individual Levels of Organization Copyright 2010, John Wiley & Sons, Inc. Life Processes Metabolism Responsiveness Movement Growth Differentiation Reproduction How body functions? Homeostasis Maintaining a stable internal environment Dynamic process because of many changes Examples of variable factors Body temperature Blood pressure Water and nutrient levels Maintained by feedback systems Components of Homeostatic Mechanisms Stimulus disrupts a controlled variable Receptor recognizes the change and sends message = input (typically by nerve pathways) to: Control Center that evaluates input and sends output to: Effector that attempts to change the altered variable Levels of Organization Negative Feedback Systems Most homeostatic control mechanisms are negative feedback systems “Negative” means “opposite” (not “bad”) These systems reverse a change in the controlled variable, bringing it back to “normal” Example: high blood pressure (BP) is detected and then lowered to normal BP Negative Feedback Systems Positive Feedback Systems Few homeostatic control mechanisms are of this type These systems strengthen a change and must be shut down by an outside force. Examples: Contractions of uterus cause even more contractions (and more…) at child birth Hormonal control of ovulation Systems that control blood clotting Aging and Homeostasis Normal process that: Includes a progressive loss in the ability to maintain homeostasis Affects all body systems Can be slowed down or minimized by healthy living Clinical Terms Disorder: abnormality of structure/function Disease: specific illness characterized by signs and symptoms Symptoms: subjective changes not observable from outside a person. Examples: pain, headache, nausea Signs: observable or measurable changes. Examples: high BP, ankle swelling, fever Autopsy Examination and dissection of a body to determine the cause of death when life processes have not been maintained adequately. Anatomical Terms Precise use of language to define position, direction, and location in the body. Anatomical position Stands erect facing the observer, with head level and eyes facing forward, and palms facing forward Common and anatomical terms Directional terms Planes and sections Body cavities Anatomical Position Directional Terms Planes Through the Human Body Planes and Sections: Brain Planes and Sections: Brain Planes and Sections: Brain 29 30