Study of how the body works to maintain life.
Definition of Physiology.
How physiology processes are altered in disease or injury.
- 1. Form a testable hypothesis about observation.
- 2. Conduct & analyze experiments to test hypothesis.
- 3. Draw a conclusion about whether or not results support hypothesis.
- 4. Develop a theory.
What is a theory.
a general statement explaining natural phenomena tht is based on a proven hypothesis.
Testing of Hypothesis involves:
- Experimental and control groups.
- quantitative measurements performed blindly.
- Analysis of data using statistics.
- Publication in peer-reviewed journals.
What is an Experimental group?
The group that is subject to the testing conditions.
What is a control group?
The group that is not participating in the experimental hypothesis.
What is analysis of data using statistics?
Employment of mathematical tools of statistics to show the the results are warrant and the null hypothesis can be rejected and the experimental hypothesis can be deemed to be supported by the study.
What is the Null Hypothesis?
The hypothesis that the difference is due to chance.
What happens in Phase I trials?
Toxicity and metabolism tested in healthy human volunteers.
What happens in Phase II Trials?
Effectiveness and toxity tested in target population (have disease).
What happens in Phase III Trails?
Widespread test of drug in diverse population.
What happens in Phase IV Trials?
Drug is tested for other potential uses.
Who is Claude Bernard (1813-1878)?
Observed that Milieu Interieur (internal environment)
Who is Walter Cannon (1871-1945)?
Coined term Homeostasis.
What is Homeostasis?
Maintenance of a state of "Dynamic Constancy"
What type of parameters have a set point?
- Arterial pH.
- Oxygen content.
- Amino Acids.
- Total Lipids.
What is a Negative Freedback Loop?
Effect on original start (stops original signal).
What is involved in a Negative feedback loop?
- set point.
- integrating center.
What does the Sensor do in NFL?
Detects deviation from set point.
What does Set Point Do in NFL?
Average of a range (a set #)
What is Integrating Center in NFL?
Determine response (brain or spinal cord most often)
What does the Effector Door in NFL?
- Produces response to decrease or increase as needed.
- (Muscles or glands).
What are the 3 types of Effectors?
- Antagonistic Effectors.
- Intrinsic Mechanisms.
- Extrinsic Mechanisms.
What is Antagonistic Effectors?
- Has antagonistic actions.
- Described as "push-pull" where the increasing activity of one effector is accompanied by decreasing activity of an antagonistic effector.
What is an Intrinsic Mechanism?
Control is built into organ being regulated
What is Extrinsic Mechanism?
Control comes from outside of organ. (Nervous & Endocrine system - nerves and hormones)
What is Positive Feedback?
The action of effectors amplifies those changes that stimulate the effectors.
What are examples of Positive Feedback?
- Estrogen levels in ovulation.
- Oxytosin in Child birth.
What is Muscle Tissue Specialized for?
What are the 3 types of Muscle tissue?
What are the characteristics of Skeletal.
- Attached to bones at both ends by means of tendons.
- Consciously controlled, Voluntary.
- Each Fiber is large and multinucleated.
- Fibers lined up parallel w/ other fibers to form bundles.
What are the characteristics of Cardiac Muscle?
- Found in the heart.
- Myocardial cells: short, branched, striated and involuntary.
- Have intercalated Disks between cells that provide mechanical and electrical interconnections.
What are the characteristics of Smooth Muscle?
- Is NOT striated; is involuntary.
- Found in many organs, tissues.
Where is smooth muscle found?
- Walls of blood vessels.
- Controled by autonomic nervous system.
What is Nervous Tissue?
- Consists of neurons and supporting or glial cells.
- Neurons are specialized for conducting electrical signals.
What are the Characteristics of Epithelial Tissue?
- Lines and covers body surfaces (inside of organs).
- Forms membranes and glands.
- Classified by 3 types of shapes (Squamous, Columnar & Cuboidal).
What does a Squamous epithelial cell look like?
What does a Columnar Epithelial Cell look like?
Taller than wide.
What does Cuboidal epithelial cells look like?
What are the two classification layers of Epithelial Cells?
- Simple membrane.
- Stratified membrane.
What are the characteristics of Simple membranes?
- one cell thick.
- Specialized for covering viceral organs.
What are the characteristics of Stratified Membranes?
- Have a number of layers.
- Specialized for protection.
How are Epithelial Cells joined?
What do Junctional complexes do?
Increase strength and create barrier.
How are Epithelial cells seperated?
- from underlying tissue by basement membrane.
- Made of chemicals to cement to other layers.
What are the characteristics of Exocrine Glands?
- Derived from epithelium cells.
- Secrete onto epithelium via ducts.
- Can be simple tubes or clusters called ACINI.
What are the characteristics of Endocrine Glands?
- No ducts.
- goes into bloodstream.
What are the characteristics Connective tissue?
- A lot of extracellular material (fluid & collagen fibers) deposited in space between its cells.
- Includes connective tissue proper, cartilage, bone and blood.
What is connective tissue proper?