Chapter 54: Community Ecology

Humans who have pets tend to be healthier than humans who do not have pets. Which of these terms applies to the relationship between a human and a pet? A. commensalism B. predation C. parasitism D. competition E. mutualism

E. mutualism In mutualism, both members of the species pair benefit; in this case the human is healthier and the pet is getting room and board.

An earthworm that feeds on the remains of plants and animals is acting as a _____. A. detritivore B. producer C. tertiary consumer D. secondary consumer E. primary consumer

A. detritivore The earthworm is feeding on the remains of dead organisms.

Consumption of which prey makes the elf owl a tertiary consumer? Select all that apply. A. praying mantis B. ants C. grasshopper

A. praying mantis The praying mantis eats ants, which are primary consumers, making the praying mantis a secondary consumer. When the elf owl eats a praying mantis, the owl is a tertiary consumer.

When a human eats a steak, the human is acting as a _____. A. secondary consumer B. tertiary consumer C. detritivore D. producer E. primary consumer

A. secondary consumer By feeding on a primary consumer, the human is acting as a secondary consumer.

Select the correct statement(s) about the transfer of food energy up the trophic levels from its source in autotrophs. A. An organism feeds at only one trophic level. B. The length of a food chain is limited by the inefficiency of energy transfer along the chain. C. Few plants have adaptations to reduce feeding by herbivores.

B. The length of a food chain is limited by the inefficiency of energy transfer along the chain.

A cow eating grass is an example of a _____. A. producer B. primary consumer C. tertiary consumer D. detritivore E. secondary consumer

B. primary consumer By feeding on a producer, the cow is acting as a primary consumer.

In an ecosystem, phytoplankton are _____. A. secondary consumers B. producers C. primary consumers D. detritivores E. tertiary consumers

B. producers Autotrophs, such as phytoplankton, are producers.

One member of the Sonoran desert food web not shown in the diagram is the roadrunner, a bird with a varied diet that includes the collared lizard, grasshopper, and praying mantis. Which trophic level(s) does the roadrunner occupy? Select all that apply. A. primary consumer B. secondary consumer C. tertiary consumer D. quaternary consumer

B. secondary consumer C. tertiary consumer The grasshopper is a primary consumer, so when the roadrunner eats a grasshopper, it is a secondary consumer. Both the praying mantis and the collared lizard are secondary consumers. When the roadrunner eats these animals, it is a tertiary consumer.

An egret eats insects stirred up by grazing animals. Which of these terms applies to the relationship between the egret and the grazing animal? A. parasitism B. competition C. commensalism D. predation E. mutualism

C. commensalism In commensalism, one member of the species pair benefits and the other is unaffected; in this case the egret is getting a meal and the grazing animals are unaffected.

In most ecological communities, plants are the first level of the trophic structure, known as producers. What do plants produce that supports the higher trophic levels of the community? A. energy B. oxygen C. energy-containing food molecules D. carbon dioxide

C. energy-containing food molecules Producers capture energy in the bonds of food molecules; consumers harvest that energy and use it for their own maintenance, growth, and reproduction.

Which of the following best describes the consequences of white-band disease in Caribbean coral reefs? A. Algal species take over and the overall reef diversity increases due to increases in primary productivity. B. Staghorn coral is decimated by the pathogen, and Elkhorn coral takes its place. C. Key habitat for lobsters, snappers, and other reef fishes improves. D. Algal species take the place of the dead coral, and the fish community is dominated by herbivores.

D. Algal species take the place of the dead coral, and the fish community is dominated by herbivores.

Caribbean coral reef communities have been strongly influenced by an unknown pathogen that causes white-band disease. How can the effect of white-band disease best be described? A. the removal of a keystone species B. Batesian mimicry C. mutualism D. a cascade event that shifts the entire makeup of the community E. commensalism

D. a cascade event that shifts the entire makeup of the community. The removal of the corals shifts the food supply within the reef, resulting in a completely different species composition.

Humans and sharks both eat fish. Which of these terms applies to the relationship between the human and the shark? A. parasitism B. commensalism C. mutualism D. competition E. predation

D. competition The human and the shark are both competing for a resource (fish).

Which of these terms applies to the relationship between a dog and a blood-sucking tick? A. competition B. predation C. commensalism D. parasitism E. mutualism

D. parasitism The tick benefits at the expense of the dog; the dog is the host and the tick is the parasite.

A human eats a deer. Which of these terms applies to the relationship between the human and the deer? A. competition B. parasitism C. mutualism D. predation E. commensalism

D. predation The human is the predator and the deer is the prey.

A human who just ate a hamburger is eaten by a shark while swimming. The shark is acting as a _____. A. secondary consumer B. primary consumer C. detritivore D. tertiary consumer E. producer

D. tertiary consumer The shark that ate the human that ate the cow that ate the grass is the tertiary consumer.