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Complete this list of things to get off to a good start: Log on to Blackboard and enter the Physio 1 class site. Review all menu links and all pages of the syllabus carefully! Make sure Blackboard has your correct email address (change through the Zone or Class-Web if necessary. Take Syllabus Quiz online by We, Aug 24th, 11:59 pm (10 pts.) Furthermore, by Aug 24th: Fill out and turn in student info sheet Introduce yourself in Bb Discussion Board Log on to Connect 10 start up pts.

Textbook – some special features: Clinical Investigation Engaging Art Interactions Chapter summary Review Activities: EOC questions Glossary and Index Connect

Ch 1: Introduction to Physiology Lesson SLOs Describe the scientific study of human physiology Describe key elements of the scientific method explain an example of a well-designed experiment Define and describe homeostasis Explain the role of antagonistic effectors in maintaining homeostasis Diagram examples of negative and positive feedback loops Explain the concept of a stem cell and list three different types. Identify the body fluid compartments

Moving beyond the genome: from genomics to proteomics Physiology is . . . . . . the study of the ___________ of all plants and animals in their ____________ state. Comparative physiology / Pathophysiology . . . an integrative science Moving beyond the genome: from genomics to proteomics

The Science of Physiology is based on the Scientific Method Review Basic steps of scientific method Parameters to consider Experimental design

Basic Steps of Scientific Method: Observation (and/or study of prior knowledge) Hypothesis Experimentation Collection and analysis of data (can you replicate results?) Conclusion: reject or accept hypothesis theory

Parameters to consider: Independent vs. dependent variables Experimental group vs. control group: only one independent variable is changed Controlled by experimenter Responds to independent variable: gives results.

Measurements, Controls, and Statistics In addtion to the above, good physiological research requires: Quantifiable measurements Statistical analysis Review and publication by a peer- reviewed journal

Independent variable ( researcher manipulates)  ? Dependent variable ( responds to independent variable)  ?

Apply scientific method: Company has found new artificial sweetener Prior knowledge: Some food additives are not safe. Hypothesis: ? Experiments: ? Collect and analyze data Conclusion

Animal vs. Human Experimentation In Physiology most knowledge is derived from _______ experimentation. Sometimes human experimentation necessary. Difficulties of Human Experimentation: Variability → very dissimilar test subjects Psychological aspects → placebo vs. nocebo effects Ethical questions → is it o.k. to withhold potential drug from seriously ill?

Developing Pharmaceuticals Basic research In vitro research Animal studies (usually rats and mice) = in _______ Animal trials may take several years. Experimental Design for Human Studies Blind study (subjects do not know if they get treatment or placebo) Double-blind study Double-blind crossover study (each subject participates in experimental AND control group)

Phases of clinical trials Phase I clinical trials: _________human volunteers to test for side effects, rates of passage, dosage, etc. Phase II clinical trials: test effectiveness on people with the particular disease. Phase III clinical trials: large #s of people; very inclusive. From here FDA can approve drug for sale. Phase IV trials test other applications for the drug. to include both sexes, many age groups and ethnicities, and people with more than the one health condition.

Many Forms of Human Studies For example: Longitudinal studies (e.g.: Framingham Heart Study) Retrospective studies (e.g.: Silent aspiration: results of 2,000 video fluoroscopic evaluations.) Meta-analysis (e.g.: Meta-analysis of soy intake and breast cancer risk)

Review Levels of Organization

Homeostasis and Feedback Control Def: __________constancy of internal environment Regulated through collaboration of body systems Many body parameters controlled via homeostatic mechanisms (?) Failure to maintain homeostasis  _____ Pathophysiology (E.g.: DM) Relative or dynamic

Negative Feedback Loops Sensors detect change and send information to the: Integrating center, which assesses change around a set point. The integrating center then sends instructions to an: Effector, which can make the appropriate adjustments to counter the change from the set-point Continuous process, constant fine adjustments to stay in normal range

Antagonistic Effectors Homeostasis often maintained by opposing effectors that move conditions in opposite directions. Antagonistic controls are used to stay near set point: Negative feedback Fig 1.3/4 A knowledge of normal ranges aids in diagnosing diseases and in assessing the effects of drugs and other treatments in experiments

Quantitative Measurements

Homeostasis Review Dynamic Constancy with Oscillation around Set Point

Negative Feedback Example

2 types of feedback loops: Negative and Positive NOT homeostatic !! Homeostatic

Baby drops lower in uterus to initiate labor Push baby against cervix Cervical stretch causing stimulates Uterine contractions Oxytocin release causes Positive feedback loop Delivery of baby stops the cycle Positive Feedback Not homeostatic! Cannot work alone, needs outside force to be shut off Helps many negative feedback loops Other examples?

Nerual and Endocrine Regulation Intrinsic regulation: Cells sense change and signal to neighboring cells  response (local pathway Extrinsic regulation: Brain or ES regulate an organ (long distance pathway) NS “innervates” organs with ___________ ES releases hormones ____________________________ Into blood and then to target organs

Control systems regulate variables Brain evaluates the change and initiates a response. Systemic change in blood pressure sensed here. LOCAL CHANGE RESPONSE Blood vessels REFLEX is initiated by cells at a distant site. In local control, cells in the vicinity of the change initiate the In reflex control, cells at a distant site control the Response Stimulus Integrating center KEY local pathways long distance (reflex) pathways

Neural Control - detailed Fig 1.6

Feedback Control of Hormone Secretions Fig 1.7

Stem cells Differentiation starts during embryonic development Totipotent zygotes Pluripotent embryonic stem cells Multipotent adult stem cells E.g.: Bone marrow cells, ....? This ability to become any type of cell in the body is called pluripotent. Thedifference between totipotent and pluripotent cells is only that totipotent cells can give rise to both the placenta and the embryo. 4. As the embryo grows thesepluripotent cells develop into specialized, multipotent stem cells.

Cell Differentiation From 1 ___________ to > 200 different types of cells Mechanism: differential gene activation 2

Body Fluid Compartments brand new human baby is 75 percent water. But then, with every step we take, we begin to dry. The longer we live, the drier we get. One year after birth, a human baby is only 65 percent water – a ten percent drop, says the U.S. Geological Survey. Babies are wetter than children. By the time we're adults, the USGS says, adult men are about 60 percent water, adult women 55 percent. Elderly people are roughly half water. Intracellular: area inside the cells; contains 65% of total body water

Clinical Investigation Primary tissues, organs, and systems: Review on your own. the end