Ecosystems: Practice Questions

In a typical food chain, which group of organisms is responsible for converting light energy into chemical energy?

In a terrestrial ecosystem, the root nodules of legume plants contain bacteria of the genus Rhizobium. These bacteria fix atmospheric nitrogen into ammonia for the plant's use, while the plant provides the bacteria with organic nutrients produced during photosynthesis. This interspecific relationship is best described as:

A forest ecosystem is undergoing secondary succession after a major disturbance. The area is currently dominated by pioneer species. However, the ecosystem is chronically exposed to high levels of atmospheric nitrogen deposition from nearby industrial sources. What is the most probable long-term ecological consequence of this persistent excessive nitrogen input on the community structure and its progression toward a climax community?

Mangrove forests are unique ecosystems found in coastal areas. Which of the following is a characteristic feature of a mangrove ecosystem?

Why is random sampling a crucial technique when studying the distribution and abundance of organisms in a habitat?

Name one type of symbiotic relationship, other than mutualism, and briefly describe how the organisms interact.

Explain how large-scale deforestation contributes to an increase in atmospheric carbon dioxide concentration.

Describe two distinct stages of primary ecological succession on a bare rock surface, highlighting the characteristic pioneer organisms and the changes they bring about.

(a) Construct a simple food chain for a terrestrial ecosystem, including at least three organisms, starting with a producer. Identify each organism's trophic level. (2 points)

(b) Explain the importance of producers to the energy flow within this ecosystem. (1 point)

(c) Name one abiotic factor that would significantly affect the growth of the producer in your food chain. (1 point)

Ecosystems are defined by the interactions between organisms and their environment, where each species plays a specific role.

(a) Define the term ecological niche and explain how it differs from a species' habitat. (2 points)

(b) Describe two different types of interspecific relationships, excluding predation, that can occur within an ecosystem. For each relationship, provide a specific example involving different species. (2 points)