Question 1

The origin of the Earth's biological diversity is embodied in the

Accepted Answer

The theory of evolution, proposed by Charles Darwin and Alfred Russel Wallace, explains how the Earth's biological diversity came to be through the process of natural selection acting on genetic variation within populations.

Question 2

Human caused eutrophication is known as

Accepted Answer

Cultural eutrophication is the process of nutrients such as nitrogen and phosphorus entering a body of water due to human activities such as agriculture and industry, leading to an excessive growth of algae and other aquatic plants. This process can cause harmful algal blooms and oxygen depletion, leading to negative impacts on aquatic ecosystems and human health. The other choices are not accurate terms for human caused eutrophication.

Question 3

When a community is disturbed to the point that most or all of its species are eliminated,a process called ____occurs in which the area undergoes a series of changes in species composition as newer communities replace older ones.

Accepted Answer

The process described in the question is ecological succession, which occurs when a disturbance completely eliminates a community and allows for new species to colonize and establish a new community structure over time. Rejuvenation refers to the restoration of an ecosystem to its previous state, patch dynamics involves the dispersal and colonization of species within a larger ecosystem, and symbiosis refers to the interaction between two different species for mutual benefit. Mass extinction is a phenomenon of a global level, where a majority of species on Earth become extinct in a short time span.

Question 4

Which of the following taxonomic groups has the highest number of known species?

Accepted Answer

Insects are the most diverse group of animals on Earth, with over 1 million known species. Fungi have around 120,000 known species, plants have around 300,000 known species, chordates have around 65,000 known species, and protozoa have around 50,000 known species.

Question 5

The variation of life encompassing species diversity,genetic diversity,and ecosystem diversity is known as

Accepted Answer

Biodiversity is the variation of life in terms of species diversity, genetic diversity, and ecosystem diversity. Option A "commensalism" refers to a type of symbiotic relationship between two species, while option B "ecological niche" refers to the role and position a species has within its environment. Option C "trophic pyramids" refers to the distribution of biomass in an ecosystem and option D "limiting factor" refers to any environmental factor that limits the growth, abundance, or distribution of an organism or a population.

Question 6

What is an ecosystem? What is the spatial scale of an ecosystem? Provide some examples of an ecosystem.

Accepted Answer

The answer of What is an ecosystem? What is the...

Question 7

If a lava flow completely denudes a mountain,leaving only bare rock,what type of succession will follow?

Accepted Answer

A lava flow completely denuding a mountain would leave behind bare rock with no soil or vegetation, making it a completely new habitat. The first organisms to colonize the area would be pioneer species, such as lichens and mosses, starting the process of primary succession. Over time, as the pioneers grow and die, their decomposing remains create soil that allows other plants and animals to move into the area, leading to further stages of succession.

Question 8

Which of the following is not considered among the greatest anthropogenic threats to biodiversity?

Accepted Answer

While novel ecosystems can still have negative impacts on local species, they are not considered among the greatest threats to overall biodiversity. The other choices, habitat loss, introduction of non-native species, air, water, and soil pollution, and climate change, are all widely recognized as major threats to biodiversity.

Question 9

When a random occurrence produces altered genetic material and inserts new traits into the inherited stream,____has occurred.

Accepted Answer

Mutation is the process in which new genetic material is produced due to a random occurrence, such as a mistake during DNA replication or exposure to radiation. This altered genetic material can then be passed on to offspring, introducing new traits or variations into the inherited stream.

Question 10

Human-built or human-modified ecosystems that may have species and habitats that have never occurred together,designed to conserve biodiversity,are known as

Accepted Answer

The term "novel ecosystems" describes ecosystems that have been altered by humans in ways that have brought together species and habitats that may not have occurred together naturally. These ecosystems are designed to conserve biodiversity, but they are not natural and are often characterized by the presence of non-native species. Patch dynamics refers to the pattern of disturbance and recovery in natural ecosystems, seres and ecological successions refer to the process of natural change over time as an ecosystem evolves. Anthropocenes refers to the current geological epoch, characterized by significant impact of human activities on the Earth's ecosystems.

Question 11

____occurs when the last individual of a species dies.

Accepted Answer

Extinction occurs when the last individual of a species dies.

Question 12

____is the term for the evolution of a new species.

Accepted Answer

Speciation is the process by which new and distinct species evolve from a common ancestor. This can occur through various mechanisms such as natural selection, genetic drift, and reproductive isolation. Vicariance refers to the splitting of a geographic range, symbiosis refers to the close interaction between two different species, extinction refers to the complete disappearance of a species, and adaptation refers to the process by which an organism becomes better suited to its environment through genetic changes.

Question 13

According to a recent study,species are going extinct at a rate ____times faster than natural pre-human extinction rates.

Accepted Answer

Species are going extinct at a rate 1000 times faster than natural pre-human extinction rates, according to recent studies. This accelerated rate is largely attributed to human activities.

Question 14

The notion that the traits that help a species survive and reproduce are passed along more frequently than those that do not (i.e.differential reproduction and adaptation)is known as

Accepted Answer

Natural selection is the process by which organisms with advantageous traits are more likely to survive and reproduce, passing those traits on to their offspring. This process results in adaptation and evolution over time. The other choices are either alternative mechanisms for evolution (punctuated equilibrium and gradualism), a disproven theory (Lamarckism), or a principle related to competition rather than evolution (competitive exclusion).

Question 15

Using Figure 19.3 and Table 19.1 as your guide,describe the net primary productivity of the area in which you live.How does this net primary productivity vary across your state (or equivalent)and broader region?

Accepted Answer

The answer of Using Figure 19.3 and Table 19.1 as...

Question 16

The first species to colonize previously disturbed or damaged ecosystems are called a(n)

Accepted Answer

Pioneer community refers to the first species to colonize previously disturbed or damaged ecosystems.

Question 17

If a forest fire destroyed the vegetation in an area,but left some vestiges of the previously functioning community and the soil intact,what type of succession would follow?

Accepted Answer

This would be an example of secondary succession because there are some vestiges of the previously functioning community (such as the seeds and root systems of surviving plants) that can help jumpstart the process of regrowth. In contrast, primary succession would occur on a completely barren landscape where there are no vestiges of a previous community or soil. Tertiary, quaternary, and quinary succession are not recognized ecological terms.

Question 18

Continental drift separating a once continuous population is an example of

Accepted Answer

Vicariance is the separation of a once continuous population due to geological or geographic changes, such as continental drift. This can lead to divergent evolution and the formation of distinct species. This is different from punctuated equilibrium, which refers to a pattern of relatively rapid evolution interspersed with long periods of stasis, and mutation, which is a genetic change that can drive evolution but does not necessarily involve population separation. Lamarckian evolution is an outdated idea that organisms can pass on acquired traits to their offspring, and orogeny refers to mountain-building processes that can also affect biogeography but do not involve population separation.

Question 19

The gradual nutrient enrichment of water bodies is known as

Accepted Answer

Eutrophication is the gradual nutrient enrichment of water bodies, typically caused by human activities such as agricultural runoff and sewage discharge. This excess nutrient input leads to excessive algae growth and oxygen depletion, disrupting the balance of the aquatic ecosystem.

Question 20

What is biogeography? What subjects do biogeographers study? What is ecology? How does biogeography vary from ecology?

Accepted Answer

The answer of What is biogeography? What subjects do biogeographers...

Quiz 19: Ecosystem Essentials