Human physiology  =  The science of the function of the human body
          and its parts.
 

    Cell  =  Basic unit of structure and function of living organisms. 

     Tissue  =  Group of cells with similar functions. 

     Organ  =  Two or more tissues joined in a structural unit to perform a 
          common function. 

     Organ system  =  Group of organs that work together to perform a 
          common function. 
 

               1.  Exchange of materials with their environment. 

               2.  Energy utilization. 

               3.  Synthesis of new molecules. 

               4.  Response to external stimuli.

               5.  Reproduction. 
 

  Cell membrane

  Separates intracellular fluid from extracellular fluid.
  Cell communication

  Nucleus

  Directs cell's activities

  Cytoplasm

  Contains water, other substances, and organelles

  Organelles

  Organized structures within the cytoplasm that
       perform specialized functions.

  Endoplasmic reticulum

  Synthesizes complex molecules (ex. proteins) for
       use by the cells

  Golgi apparatus

  Sorts and packages molecules made by the
       endoplasmic reticulum

  Mitochondria

  Converts energy from nutrients to ATP
  Consumes oxygen (cellular respiration)

  Lysosomes

  Break down cellular debris and foreign material.

  Cytoskeleton

  Maintains cell shape and movement.

     1.  Muscle.

          Function:  Contraction and movement.

          Characteristics:  Elongated; composed of contractile filaments, 
               sometimes organized into dark and light bands (striations). 

          Examples*  (click on name for slide): 

               Smooth muscle
               Skeletal muscle
               Cardiac muscle

     2.  Nerve.

          Function:  Initiation and transmission of electrical impulses. 

          Characteristics:  Large cell body; branching processes (called axons
               and dendrites). 

          Examples: 

               Neuron
               Spinal ganglion

     3.  Epithelium.

          Function:  Selective transfer of materials. 

          Characteristics:  Cells lie close to one another; arranged in single or
               multiple layers; covers body surface and lines hollow organs. 

          Examples: 

               Stratified squamous epithelium
               Simple cuboidal epithelium

     4.  Connective tissue.

          Function:  Connecting and supporting body structures. 

          Characteristics:  Large amount of extracellular material; 
               sometimes appears disorganized. 

          Examples: 

               Elastic tissue
               Bone

     *  Slides are from the Loyola University Lumen Histology  Slide Series
 

     Nervous

     Muscular

     Skeletal

     Digestive

     Integumentary

     Circulatory

     Immune

     Urinary

     Respiratory

     Endocrine

     Reproductive

     1.  Cells must have a stable environment. 

     2.  Claude Bernard introduced the concept of the constancy of  the
          internal environment (1865). 

     3.  Homeostasis  =  Maintaining a constant internal environment
          in spite of changes in the external environment. 

     4.  Homeostasis is the central theme of physiology. 
 

  
               1.  Controlled variable. 

               2.  Sensor. 

               3.  Control center. 

               4.  Set point. 

               5.  Effector. 
 

     1.  Negative feedback loop.

          a.  When a change in the controlled variable triggers a response that
               opposes the change. 

          b.  Maintains homeostasis. 

          c.  Examples.
 
 

     2.  Positive feedback loop.

         a.  When a change in the controlled variable triggers a response that
              sustains or accelerates the change. 

         b.  Brief or destructive. 

         c.  Examples.
 
 

THE NATURE OF SCIENCE

          All scientific knowledge is a collection of best guesses or hypotheses

               based on what scientists have observed.

          Hypothesis  =  A tentative and general explanation of a group 
               of observations.
 

  
             A.  Dissection.

               1.  Galen.
 
           B.  Scientific revolution  (late 1500's and early 1600's).

               1.  Importance of experimentation and mathematics in the advancement
                    of scientific knowledge.
  
               2.  William Harvey.
  

  
          1.  Ask a question or identify a problem. 

          2.  Make observations related to the question. 

          3.  Formulate a testable hypothesis. 

          4.  Perform experiments to test the hypothesis. 

          5.  Analyze the results and draw conclusions.