Introduction - Chapter 1, Chapter 4, pp. 76 - 78!
Anatomy and Physiology!
•  Structure and function!
Properties of life!
• 
• 
• 
• 
Nucleic acids, proteins, CH2O, lipids!
Composed of cells!
Reproduction!
Metabolism!
ü  Anabolism!
ü  Catabolism!
1!
Properties of Life - 2!
• 
• 
• 
• 
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Responsiveness/excitability!
Maintain homeostasis (what is this?)!
Differentiation!
Growth!
Inheritance!
–  DNA!
–  Adaptive traits!
2!
1!
Levels of Organization!
A. Chemical (molecular) level!
•  Atoms, molecules!
B. Cellular level!
•  The basic structural and functional unit of
life!
•  Contain organelles!
C. Tissues level!
•  Groups of similar cells that work together to
carry out specific functions!
•  4 basic tissue types!
3!
Levels of Organization - 2!
D. Organ level!
•  Composed of two or more tissue types!
•  Structures of particular shape!
•  Have particular functions!
E. Organ systems level (Figure 4.6)!
•  Two or more organs!
•  Have particular functions!
F. Organism (individual)!
G. Population, community, ecosystem, biosphere!
4!
2!
Organ Systems - 1 "
"
"
Figure 4.7 top!
5!
Organ Systems - 2 "
"
"
Figure 4.7 bottom!
6!
3!
Homeostasis - the Core Principle of Physiology!
See Chapter 4, pp. 82 - 85!
Definition:!
•  Maintenance of relatively constant conditions
in the internal environment in the face of
environmental change!
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Relatively constant?!
!
Internal environment?!
7!
Physiological Control Systems!
Involve nervous and/or endocrine systems!
Elements:!
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Receptor!
!
Integrator (Controller)!
!
Effector!
8!
4!
Controller (Integrator)!
Controller (or Integrator)!
•  Determines the set point!
"Set point = the desired value of a controlled
variable!
•  Receives information from Receptor!
•  Computes an error signal!
" "Error signal = (actual value - desired value)!
•  Sends appropriate instructions to Effector!
9!
Receptor!
Receptor!
•  Monitors the actual value of a controlled
variable!
•  Constantly sends information to Controller!
•  E.g. thermoreceptor, chemoreceptor!
•  Does not “know” what the value should be"
!
10!
5!
Effector!
Effector!
•  Receives instructions from Controller!
•  Effects a change in the controlled variable!
•  E.g. sweat gland, skeletal muscle, smooth
muscle!
11!
A Homeostatic Mechanism
"
"
Figure 4.12!
?!
Error!
signal!
Set point!
12!
6!
Body Temperature Control System
Figure 4.13!
Controlled variable;!
Set point;!
Error signal!
13!
Types of Control Systems!
1. Negative feedback - most common type!
•  Response is opposite to stimulus!
" "e.g. blood pressure, body temp. control!
2. Positive feedback!
•  Response is in same direction as stimulus!
" "e.g. parturition (birth process)!
14!
7!
The Scientific Method!
1.  Make an observation about nature and ask a
question!
2.  Formulate a testable hypothesis!
3.  Make a prediction based upon the hypothesis!
4.  Test the prediction with controlled
experiments!
•  Control group!
•  Experimental group!
•  Large sample sizes!
15!
Scientific Method - 2!
5. Analyze data!
6.  Come to a conclusion!
•  The data do or do not support the hypothesis!
•  If yes, “so far so good,” but…!
ü  Does not prove that hypothesis is correct!
•  If no, !
ü  Hypothesis is incorrect!
ü  Errors with method, data collection,
analysis!
7.  Report conclusion!
16!
8!
Francesco Redi’s Maggots!
Observation?!
Question?!
Hypothesis?!
Prediction?!
Experiment!
•  Control group!
•  Experimental group!
!
17!
Science Terms, Limits to Science!
Hypothesis!
!
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Theory!
!
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Limits to science!
18!
9!