Download 12/01/08

12/01/08
SI A ECL 365
1.
What are organismal constraints?
a. Ionic constituents, pH, salinity, Temperature
2.
Organismal constraints have broad / narrow limits? (circle one)
a. Narrow
3.
What are things that modify the rate of heat flow?
a. External insulation (fur, feathers), peripheral blood flow, area in contact
with the source/sink, color.
4.
What type of vertebrates display variable body temperatures?
a. Poikilotherms
5.
What type of vertebrates exhibit non-variable body temperature?
a. Homeotherms
6.
In this type of vertebrate, temperature is obtained from its own oxidative
processes.
a. Endothermic
7. The temperature in this type of organism is determined by the temperature of the
environment.
a. Ectothermic
8.
True / False Core temperatures are generally the same as surface temperatures.
a. False
9.
When is heat produced and lost?
a. Heat energy produced – when food is metabolized
b. Lost – when environment is colder than animal
10. What is responsible for temperature regulation?
a. Hypothalamus and skin heat receptors
11. True / False Mammals are completely homoeothermic at birth.
a. False
12. What is Bergmann’s rule?
a. In closely related group of birds or mammals, those living in cold areas
will be larger than those living in warmer areas.
13. What ratio does Bergmann’s rule take advantage of?
a. Surface area to volume
14. Is there a lower limit on endotherms? If so, what?
a. Yes – shrew
15. What are ways of dealing with cold?
a. Increase heat production, decrease thermal conductance, (behaviorally)
avoid low temperatures, daily or seasonal relaxation of thermal
homeostasis
16. What are adaptations to cold?
a. Antifreeze, shorter appendages, darker color of paws, nose, ears
17. What allows “antifreeze” to function in vertebrates?
a. Glycoproteins in blood allow fish to survive at -1.8 degree C
18. How is heat loss avoided in vertebrates?
a. Insulation in birds and mammals (fur, feathers, blubber), anterior
hypothalamus regulates through shivering and vasoconstriction, huddling
or curling up, nest construction, counter current heat exchange
19. What are ways of staying warm in water?
a. Blubber, surface to volume ratio, trapping air in fur (skin doesn’t get wet,
but appendages do)
20. Does exercising in the cold make small organisms warmer? Why?
a. No, disturbs insulative value of fur, increases peripheral circulation which
increases heat loss
21. Describe non-shivering thermogenesis.
a. Heat production without increased muscular activity, brown fat cells have
abundant mitochondria and generate heat by oxidation of fatty acids
(found in neck, thorax, major blood vessels)
22. What is more difficult to deal with, heat or cold?
a. Heat
23. What are problems associated with dealing with high temperatures?
a. Endogenous heat produced by animals must be moved against temperature
gradient (losing heat to a hotter environment)
24. What allows heat loss to a hotter environment?
a. Water loss
25. What is convection?
a. Air temperature and wind
26. What is radiation?
a. Solar and thermal energy emitted from organism and surrounding surfaces
27. What is conduction?
a. Temperature conductance of solid surfaces in contact with organism
28. Heat stored = ?
a. metabolic heat + convection + radiation – evaporation
29. Describe countercurrent heat exchange in vertebrates.
a. Used to retain or lose heat
b. Warm blood from artery warms veins
c. Artery and vein lie side by side or tangled bundles
d. Found in marine, monotremes, sloths, armadillo, beaver, anteaters, rabbit,
arctic wolves
30. What are examples of heat adaptations found in:
a. Carnivores – panting and salivation and stretched out underside
b. Ungulates – sleek, glossy, light colored hair
c. Camels – allow body to heat up during the day and head dissipates during
night (daily fluctuations), store fat in hump, thick fur
d. Water buffalo – wallow during heat of the day
e. Bovids – horns can vasodilate in hot environment – cover them with moist
sand or mud
f. African Oryx - countercurrent exchange through nasal passage
31. What is the thermal neutral zone?
a. Temperature zone in which an animal requires the minimum amount of
energy for temperature regulation.
b. Body temp is regulated by changing effectiveness of body insulation
32. What must occur when an animal experiences lower critical temperature?
a. Must increase heat production
33. What must occur when animals experience upper critical temperature?
a. Heat cannot be dissipated fast enough.
34. What are thermal issues for herps?
a. No insulation, generate metabolic heat, basking for heat-gain, coloration
patterns help absorb/reflect solar radiation, evaporative cooling is
significant (in amphibians), impermeable integument (reptiles) allows sun
exposure without water loss, lightening/darkening integument, changing
heart rate, panting, salivation, urination and defecation on limbs and body,
sun basking done to aid digestion, bask in upper warmer waters,
countercurrent circulatory systems and oil-filled skin