Concept: Countercurrent Exchange7m
Distinguish between ectothermic and endothermic animals. Give at least three examples of each. Discuss at least two behavioral mechanisms that endothermic animals have that aid them in thermoregulation.
The temperature-regulating center of vertebrate animals is located in the ________.
a. thyroid gland
c. subcutaneous layer of the skin
Most land-dwelling invertebrates and all of the amphibians ________.
a. are ectothermic organisms with variable body temperatures
b. alter their metabolic rates to maintain a constant body temperature of 37°C
c. are endotherms but become thermo-conformers when they are in water
d. become more active when environmental temperatures drop below 15°C
An example of an ectothermic organism that has few or no behavioral options when it comes to its ability to adjust its body temperature is a ________.
a. sea star living deep in the ocean
b. bass living in a farm pond
c. hummingbird flying through a prairie
d. honeybee in a hive on a rural farm
In a cool environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm ________.
a. maintains a higher basal metabolic rate
b. expends more energy per kilogram of body mass than does the endotherm
c. invests little energy in temperature regulation
d. has greater insulation on its body surface
What would be an advantage for an animal that conforms to a changing environmental condition, such as temperature?
a. The animal's internal temperature would remain constant, even though the external temperature had changed.
b. The animal's internal temperature would change opposite to the change in the external temperature.
c. The animal would spend more time looking for food.
d. The animal would spend less energy regulating its internal temperature.
You arrive back home from a long run on a cool February morning your faced is red. This helps you to
a. stay warm and keep your muscles working
b. loose heat faster
c. use evaporative cooling
d. circulate more blood to your brain
e. conserve body heat in the cool environment
On a hot summer day your dog's tongue is hanging out her mouth. She is using ____ to thermoregulate.
Marine iguanas on Galapagos rest on black rocks after coming out of the ocean. This helps them use ____ to thermoregulate.