1.
Primary succession almost always begins with:
Correct Answer
B. Bare rock
Explanation
Primary succession almost always begins with bare rock because it is the starting point for colonization by pioneer species. Bare rock lacks organic matter and nutrients, making it inhospitable for most plants and animals. However, over time, weathering and erosion break down the rock, creating a thin layer of soil. This soil, along with the accumulation of organic matter from pioneer species like lichens and mosses, provides a foundation for the establishment of other plant species. As these plants grow and die, they further contribute to soil development, allowing for the colonization of more complex organisms and the progression of succession.
2.
If a forest fire completely destroys the plant and animal life in a forest, what kind of succession will eventually start restoring it.
Correct Answer
B. Secondary Succession
Explanation
Secondary succession is the correct answer because it refers to the process of ecological succession that occurs in an area that has been previously inhabited by plants and animals but has undergone a disturbance, such as a forest fire. In secondary succession, the soil is still present, allowing for the reestablishment of plant and animal life through the colonization of species from nearby areas. This process typically occurs faster than primary succession, which involves the colonization of barren land with no preexisting soil.
3.
The first species to inhabit a barren environment are:
Correct Answer
A. Pioneer species
Explanation
Pioneer species are the first organisms to colonize and inhabit a barren environment. They are able to survive and grow in harsh conditions, such as on bare rock or after a volcanic eruption. These species are usually hardy and can tolerate extreme temperatures, lack of nutrients, and lack of water. They play a crucial role in the process of ecological succession, as they gradually transform the environment and make it more suitable for other organisms to thrive. By establishing themselves in a barren environment, pioneer species pave the way for the establishment of a community of organisms.
4.
How long does secondary succession take before it reaches a climax community?
Correct Answer
B. 100 years
Explanation
Secondary succession is the process of ecological succession that occurs in an area that has been previously disturbed or disrupted, such as after a fire or clear-cutting. It involves the gradual establishment and development of a new community of organisms. The climax community is the final and stable stage of succession, where the community has reached a state of equilibrium. The answer of 100 years suggests that it takes approximately a century for secondary succession to progress and reach a climax community in the given context.
5.
What is an example of a pioneer species?
Correct Answer
D. Lichen/Moss
Explanation
Lichen and moss are considered pioneer species because they are the first organisms to colonize barren or disturbed environments. They are able to survive in harsh conditions and are often the first step in the process of ecological succession, paving the way for other plant species to establish themselves. Lichen and moss are able to break down rocks and create soil, making the environment more hospitable for other plants to grow. Therefore, they play a crucial role in initiating the colonization and development of an ecosystem.
6.
A glacier retreating would result in what type of succession?
Correct Answer
A. Primary Succession
Explanation
When a glacier retreats, it leaves behind a barren landscape devoid of any life. This creates a perfect environment for primary succession to occur. Primary succession is the process of colonization and establishment of plant and animal life in an area that was previously devoid of any life. In this case, the exposed rock and soil left behind by the retreating glacier would be colonized by pioneer species such as lichens and mosses, which gradually pave the way for the establishment of more complex plant and animal communities. Therefore, the correct answer is Primary Succession.
7.
Which of the following would lead to secondary succession?
Correct Answer
C. Volcanic eruption
Explanation
Secondary succession occurs in areas where an ecosystem has been disturbed but where soil remains intact, allowing for the regrowth of plants and the gradual return of animal life. A volcanic eruption can lead to secondary succession depending on the nature of the eruption and the extent of lava or ash coverage. When a volcano erupts, it often emits ash and lava. If the eruption is moderate and does not completely destroy the soil structure (for example, by depositing a layer of ash rather than obliterating the area with thick lava flows), the soil beneath can remain viable. This ash can also add nutrients to the soil, which can be beneficial for the regrowth of plant life. As the ash settles and mixes with the existing soil, it creates a fertile environment for the seeds and spores of plants to germinate and grow. These initial plants are usually fast-growing species that can thrive in nutrient-rich but unstable soils, helping to stabilize the environment further. Over time, as more plants establish, the area becomes suitable for a broader range of species, including shrubs and trees, which contribute to the recovery of the ecosystem. This gradual return of plant and eventually animal life exemplifies secondary succession, as the community builds upon the pre-existing soil substrate. Thus, a volcanic eruption can indeed set the stage for a dynamic but natural recovery process in the ecosystem.
8.
Which type of succession takes longer?
Correct Answer
A. Primary Succession
Explanation
Primary succession takes longer than secondary succession because it occurs in areas where there is no existing soil or vegetation. In primary succession, the process starts from bare rock or barren land, and it takes a longer time for organisms to colonize and establish themselves in such harsh conditions. This is because primary succession involves the gradual breakdown of rocks and the development of soil, which takes a considerable amount of time. In contrast, secondary succession occurs in areas where there is already existing soil and vegetation, so the process of recolonization and establishment of new species is faster.
9.
If no natural disasters go through a specific area over a long period of time, that area would reach a climax community.
Correct Answer
A. True
Explanation
If no natural disasters occur in a specific area for a long period of time, the ecological succession in that area will continue undisturbed. This means that the community of plants and animals in the area will gradually reach a stable and mature state known as a climax community. In a climax community, the species composition and structure of the community remain relatively constant, with a balance between birth and death rates. Therefore, the statement that an area would reach a climax community if no natural disasters occur is true.