38. Animal Form and Function

True or False: The increase in red blood cell count in tourists visiting Tibet is an example of acclimatization.

What are three attributes of mitochondria and chloroplasts that suggest they were once free-living bacteria?

Which of these examples best describes the concept that form facilitates function?

a. Crickets must balance their resources between spermatophore production and immune defenses.

b. A desert jackrabbit has large ears that help eliminate excess heat.

c. An Antarctic fish maintains homeostasis by conforming to the stable, external temperature.

d. Honeybees will swarm around a predatory wasp and contract their flight muscles to generate a lethal ball of heat.

Consider the energy budgets for a human, an elephant, a penguin, a mouse, and a snake. The would have the highest total annual energy expenditure, and the would have the highest energy expenditure per unit mass.

a. Elephant; mouse

b. Elephant; human

c. Mouse; snake

d. Penguin; mouse

The cells of an ant and an elephant are, on average, the same small size; an elephant just has more of them. What is the main advantage of small cell size? (Explain your reasoning.)

a. A small cell has a larger plasma membrane surface area than does a large cell.

b. Small cells can better take up sufficient nutrients and oxygen to service their cell volume.

c. It takes less energy to make an organism out of small cells.

d. Small cells require less oxygen than do large cells.

Which of the following statements regarding surface area and volume in animals are correct? Select True or False for each statement.

T/FAs an animal grows, its volume increases more rapidly than its surface area.

T/FA chihuahua has a higher surface area to volume ratio than a Great Dane.

T/FAnimals with high surface area to volume ratios heat and cool more slowly than animals with lower surface area to volume ratios.

T/FAs an animal's volume increases, its total surface area decreases.

Compared with a smaller cell, a larger cell of the same shape has

a. Less surface area

b. Less surface area per unit of volume

c. The same surface-area-to-volume ratio

d. A smaller cytoplasm-to-nucleus ratio

Negative-feedback mechanisms are

a. Most often involved in maintaining homeostasis.

b. Analogous to a furnace that produces heat.

c. Found only in birds and mammals.

d. All of the above.

Which of the following cell structures would you expect to be most important in the growth of bacteria on the surface of your teeth?

a. Cell wall

b. Fimbriae

c. Flagella

d. Cilia

Which of the following best illustrates homeostasis? (Explain your answer.)

a. Most adult humans are between 5 and 6 feet tall.

b. All the cells of the body are about the same size.

c. When the salt concentration of the blood goes up, the kidneys expel more salt.

d. When oxygen in the blood decreases, you feel dizzy.

Draw a model of the control circuit(s) required for driving an automobile at a fairly constant speed over a hilly road. Indicate each feature that represents a sensor, stimulus, or response.