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Research on Thursday afternoon are encouraged to contact Dr. Davis

• Study questions will be updated to be consistent with 11th edition of the text.

• Contact Dr. Davis regarding changes in lab days.

• Check email for first assignment due Friday.

Homeostasis:

• The relative constancy of the internal environment

• Steady state vs. equilibrium

The body: A society of interdependent cells, each type with its own needs and contributions.

O2

Cell Membrane: selectively permeable

Capillaries: highly permeable except to proteins

Homeostasis

• Regulated via reflex arcs and naturally maintained by the process of negative feedback

• Measurement– Which physiological variables?– Averages and ranges

Fig. 01.08

Thermoregulation

Physics of thermal energy flow

Cell metabolism=main source of heat

• Conduction

• Convection

• Evaporation

• Radiation

Mechanisms of thermoregulation

For constant body temp heat in = heat out

• Reflex arc

• Negative feedback

• Examples

• Acclimatization vs. adaptation