I. Animal Physiology
A. Biological science
B. How animals work
C. Studied at varying levels of organization
II. Why should one study animal physiology?
A. Biology fundamentals, health, culture
B. Interdisciplinary
1. Biomechanics
2. Physics
3. Morphology
4. Nervous Control
5. Electrophysiology
6. Biochemistry
III. Physiological processes contribute to survival
A. Mechanistic vs. teleological explanations
B. Mechanistic physiology explanations
C. Evolutionary physiology explanations
D. Environmental physiology explanations
IV. Internal environment and homeostasis
A. Homeostasis is the maintenance of internal constancy
B. Homeostasis is central to understanding physiology
C. Most cells in multicellular organisms are in an internal environment
D. Dynamic equilibrium with small internal fluctuations
E. Negative feedback systems help control homeostasis
-Opposite effect
-The variable being regulated (temperature, salinity, etc.) brings about responses that move the variable in a direction opposite of the direction of the original change
-Involves sensor, control center and responder
-Examples include body temperature and stimulus-response reflexes
[-Positive feedback is different, in that it quickly maximizes changes in the regulated variable]
F. Conformity
-Loss of homeostasis
-Temperature of salmon as water temperature changes
G. Regulation
-Constancy with internal chloride concentrations in salmon
-Regulators use mechanisms to regulate their internal environment over a range of external environment changes
-Strive for a zone of stability