38. Animal Form and Function

Which of the following is a description of a behavior that helps warm the body?

During a fever, the __________ readjusts the set point of the body to a __________ temperature.

Sweating __________.

In the late fall, bats hibernate in clusters with many bats pressed together and holding on to one another. Which of the following statements does not represent an advantage of this behavior?

On a cold day, blood vessels in the skin __________.

By definition, an ectotherm __________.

The term endotherm refers specifically to __________.

Which statement is true regarding thermoregulation?

The wolf, his coat glowing in the early spring sunshine, sat atop a cold boulder after unsuccessfully pursuing a plump jackrabbit. He continued to pant while __________.

It is a cold day in the lecture hall. When you rest your arm on the cool laminated desktop at your seat, heat is transferred __________.

Which of the following statements is true?

Which of the following is not an adaptation for reducing the rate of heat loss to the environment? a. feathers or fur b. increasing blood flow to surface blood vessels c. huddling behavior of penguins d. countercurrent heat exchange

Consider three spheres with radii of 1 cm, 5 cm, and 10 cm. Calculate the surface area and the volume of each sphere, and plot the results on a graph with radius on the x-axis and surface area and volume on the y-axis. (Surface area of a sphere = 4πr2; volume of a sphere = (4/3)πr3.) Explain how the graph shows the relationship between size and surface area to volume ratio.

After a long, hot run together, your friend tells you that you should dunk your head into a cooler of water to lower your body temperature more rapidly, rather than sitting and waiting to cool down. What do you think? Form a hypothesis about how the ice-cold water might affect the rate at which your body temperature returns to normal. How could you test your hypothesis?

You are in a room of empty chairs. As the chairs fill with people, you become hotter and hotter. A ceiling fan is turned on, and you feel cooler. You gained heat by _________ and lost heat to the environment by _________ . a. conduction … convection b. radiation … convection c. radiation … conduction d. convection … radiation

Can ectotherms have stable body temperatures? Explain.

Some diuretics are on a list of substances that the International Olympic Committee has banned for use by athletes. What do diuretics do? Propose an explanation for how diuretic use could be an unfair advantage for a competitor in a sport like wrestling, in which weight classes are part of the competition.

You are studying a large tropical reptile that has a high and relatively stable body temperature. How would you determine whether this animal is an endotherm or an ectotherm?

Dolphins have an insulating layer of blubber that protects them from cold water, but their flippers are not insulated. Propose a hypothesis to explain why dolphin flippers do not freeze. Describe an experiment you could do to test your hypothesis. (You may assume you have equipment for measuring temperatures in dolphin flippers.) What results would you expect if your hypothesis is correct?

In 1847, the German biologist Christian Bergmann noted that mammals and birds living at higher latitudes (farther from the equator) are on average larger and bulkier than related species living at lower latitudes. Suggest an evolutionary hypothesis to explain this observation.