Lecture 1 - Introduction PDF

Homeostasis : 1. Syllabus 2. Brief intro to Physiology and Anatomy. 3. History of Have a question? JUST ASK  OFFICE HOURS Monday 1:30-2:30pm ([email protected])  Physiology 1. The study of the healthy functioning of a living organism and its component parts 2....

Homeostasis : 1. Syllabus 2. Brief intro to Physiology and Anatomy. 3. History of Have a question? JUST ASK  OFFICE HOURS Monday 1:30-2:30pm ([email protected])  Physiology 1. The study of the healthy functioning of a living organism and its component parts 2. Includes all its chemical and physical processes 3. Helps to have a basic knowledge of anatomy 4. Organization of life: the cell is the smallest unit of structure capable of carrying out all life processes 5. Atoms, molecules, cells, tissues, organs, organ systems, and organisms Physiology is a very broad topic!!  Themes in Physiology 1. Structure and function are related – Molecular and cellular interactions – Compartmentalization of functions – Cell and tissue shape 2. Living organisms uptake energy and produce waste 3. Cell membranes are critical 4.Homeostasis maintains internal  Why is homeostasis useful? 1. It enables the body to be internally stable. – Biochemical function occur at optimal levels. Homeostasis is a terrific evolutionary advantage as this optimal environment (the body) is portable. 2. It enables an organism to be more independent of its environment. – This enables the body to operate in sub-optimal environments. 3. It enables physiology to be partially changed by changing the homeostatic environment during times of need. (i.e. fever) The body can be thought of as a group of organ systems These are composed of different cell types, related by a common function. How do organs relate to HOMEOSTASIS?  To maintain homeostasis, usually multiple organ systems are involved This course will explore the molecular mechanisms underlying homeostasis and thus some of the anatomy as well.  Organ systems Homeostasis, in part, is the common function of all the organs of the body. All of the systems you learn about in Physiology contribute to Homeostasis.  Organ systems The circulatory system will be the key organ system in our Case Study of fluid balance. As well as it is the vehicle for nearly all cell signaling that occurs in all forms of homeostasis.  Organ systems The digestive system will be important in our Case Study of metabolism and the microbiome.  Organ systems The endocrine system is involved in many aspects of homeostatic signaling. It is also key to our understanding of Circadian Rhythms  Organ systems The immune system is not a classical example of homeostasis but is included in this course because new information about the microbiome indicates it has some of the features of a  Organ systems The integumentary system is an important component of Thermoregulation. The maintainance of our tissues is also thought to be homeostatic, and this will be covered as well.  Organ systems The musculoskeletal system is an important component of Ca2+ and glucose homeostasis.  Organ systems The urinary system will be a subject in our Case Study of fluid and ion homeostasis. What tissue is this? Pancreas  Endocrine system Responsible for chemical signaling and coordination of homeostasis between What tissue is this? Artery  Circulatory system Responsible for the movement of chemicals and cells throughout the body What tissue is this? Sweat Glands Integumentary system Responsible for external protection of the body... Also to regulate temperature What tissue is this? Small intestine  Digestive system Responsible for the uptake of nutrients from the environment and their distribution to the other tissues of the body.  What tissue is this? Lung macrophages (smoker)  Immune system Responsible for the defense of the body from pathogens Claude Bernard (1813-1878) Worked to establish the scientific method in the study of medicine. Double-blind experiments. Life is subject to same laws as inanimate objects. Milieu interieur. Claude Bernard Milieu interieur. (1813-1878) “The living body, though it has need of the surrounding environment, is nevertheless relatively independent of it.” “..a free and independent existence is possible only because of the stability of the internal milieu.” “The constancy of the internal environment is the condition for free and independent life: the mechanism that makes it possible is that which assured the maintenance, within the internal environment, of all the conditions necessary for HOMEOSTASIS = maintaining a constant internal environment. Walter Cannon (1871-1945) Fight or flight response. Heavy metal labeling in X-rays. Homeostasis. Walter Cannon Features of (1871-1945) Homeostasis. 1. Homeostasis does not occur by chance, mechanisms in the body are present to maintain homeostasis. 2. A tendency to change must be met with factors that resist that change. 3. The homeostatic state consists of a number of cooperating mechanisms that occur at the same time, or in succession. 4. Considered both active and passive aspects of homeostasis. HOMEOSTASIS = mechanisms of physiology that work to maintain a constant internal environment. Homeostasis = maintenance of a constant internal environment. Critical variables Physical and chemical factors that affect cells How cells communicate with one another Homeostasis is within a range of values, not a single value. Disease / pathology Failure to maintain homeostasis Study of body functions in disease is called pathophysiology Example: diabetes mellitus – abnormally high blood