Biology 112 Quiz: Chapters 53 Name________________________

1. (2 points) What distinguishes a keystone predator from a ‘regular’ (non-keystone) predator?

Keystone predators have disproportionate effects on community diversity relative to their abundance

2. (2 points) If 2 species have completely overlapping fundamental niches, asymmetric competition and they are sympatric, what is a likely consequence?

Competitive exclusion

3. (1 point) Resource partitioning is best described by which of the following statements?

a) Competitive exclusion results in the success of the superior species

b) Slight variations in niche allow closely related species to coexist

c) Two species can coevolve and share the same niche

d) Species diversity is maintained by switching between prey species

4. (1 point) Which of the following is an example of overgrowth competition?

a. Pale-leaved sunflowers exclude other plants in the soil by growing mats of dense root

systems.

b. Where moose occur, they exclude deer because they are taller.

c. In the wild, Joe-Pye weed grows in wetlands, but in cultivation it can grow in normal

garden soil.

d. In tropical rain forests, tall canopy trees suppress growth of seedlings and saplings by

shading them.

5. (1 point) All of the following are possible explanations for why herbivores eat so little of the food available to them EXCEPT:

a) that plants could defend themselves effectively against attack.

b) that plant tissues could offer poor or incomplete nutrition.

c) that herbivores could be kept in check by predation and disease.

d) that herbivores prefer a variety of plants and thus do not overstress a species.

6. (1 point) Biologists have suggested that changes within a parasite can manipulate the behavior of the host. Which of the following supports that hypothesis?

a) In liver cells that are infected by Plasmodium, HLA-B53 proteins bind to a particular protein found in sporozoites.

b) Flukes are known to use both snails and birds as host for different phases in their life cycle.

c) Snails infected with flukes become attracted to light, even though uninfected snails avoid sunlit areas and prefer shady environments.

d) When certain strains of Plasmodium are found together, the HLA-B53 proteins may not be able bind to a particular protein found in sporozoites.

7. What conclusion can be drawn from this graph produced during a recent study

of the fire history of giant sequoia groves in California?

a. Giant sequoias grow in small, isolated groves on the west side of the Sierra Nevada range.

b. Biologists now let low-intensity fires burn instead of suppressing them immediately.

c. The rate of fires remained steady over the past 2000 years, most likely due to the

interference of humans.

d. The rate of fires decreased over the past 400 years, most likely due to the interference of humans.

8. Which event would be considered primary succession?

a. The logging of an area leaves only the soil.

b. A flood removes all of the mammals from an area.

c. A landslide causes the removal of the soil and its organisms and the removal of the

organisms that live above the soil, leaving rock exposed.

d. Following a succession event, a specific sequence of species begins to appear.