LECTURE I:

1. Describe some evolutionary factors that alter the low (or upper) thermal tolerance of ectotherms?
2. What are the main effects of low (or very high) temperatures on animals?
3. Why do extracellular fluids freeze first?
4. What is the difference between freeze tolerance and freeze avoidance? Which of these two adaptations would an animal use if it needed to be active in cold weather?
5. What is a Q10? Does a given animal have a single Q10 for all physiological activities and all temperature ranges?
6. How does physiological performance typically change in animals betweeen the CTMin (critical thermal minima) and CTMax temperatures?
7. Why is developmental temperature such an important variable to organisms? How do the thermal tolerances of juveniles and adults compare?

LECTURE II

1. Write out a heat balance equation (include radiation, convection, conduction, metabolism evaporation) and use symbols (+, -, or ±) to indicate whether the heat exchange can be to or from (or both) the animal. What are the various mechanisms of heat exchange that cause heat gain or heat loss? What are the basic principles involved in heat transfer?
2. What is the difference between conduction and convection?
3. Why is it hard for a tiny ectotherm to gain heat by basking in the sun?
4. How does the amount and the wavelengths of emitted radiation change as a function of skin temperature on an animal? Could you use this knowledge to estimate the skin temperature of an animal?
5. Why is color more influential to the thermal balance of a large than a small animal?
6. A small and a large lizard begin basking early in the morning. Graph how their body temperatures will change. Assuming that both have same Tset, which will seek shade sooner and why? [The same problem applies to different size body parts of an animal (e.g., leg vs. trunk).]
7. Imagine a lizard and a mouse sitting in the sun on a cool day. Graph how the lizard's temperature will change (and the mouse's metabolic rate) change as wind speed increases?
8. Why is the lower critical temperature of an endotherm inversely related to body mass?
9. Why is using evaporative cooling a dangerous strategy for most desert animals? Given this problem, would you expect to see many desert animals running around in sun at high noon in summer?
10. Consider a basic biophysical model of heat transfer. Why is heat balance coupled with water balance of an animal and its mass balance (i.e., whether it gains or loses mass)?

LECTURE III

1. What are some behavioral and physiological adjustments that animals use to regulate temperature? For each, be able to say which avenue of heat exchange it uses (e.g., sweating works via evaporative cooling, color works via affecting radiation absorption.

BE SURE TO READ THE TEXT ABOUT COUNTER CURRENT HEAT EXCHANGERS ñ understand how they minimize heat loss (e.g., from a seal's flipper) in a cold environment.

Understand the basic considerations necessary for temperature regulation (sensor, set-point, negative feedback).

What is the role of the hypothalamus in temperature regulation?

What happens to Tset and to Tb during fever? What is the adaptive significance of fever?