Question 1

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

Accepted Answer

Primary succession is the type of succession that occurs on bare rock or surfaces that have never been colonized before. In this scenario, the lava flow has completely denuded the mountain, leaving only bare rock, which means that no organisms exist in the area. As a result, primary succession will occur as the first organisms to colonize the area will be pioneer species like lichens and mosses that can grow on bare rock. Over time, these pioneer species will break down the rock and add organic matter to the soil, allowing for other plants and animals to gradually move in and establish a more complex ecosystem.

Question 2

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

Accepted Answer

Mutation is the only answer choice that accurately describes a random occurrence producing altered genetic material and inserting new traits into the inherited stream. Lamarckian evolution involves the idea that acquired traits can be passed down to offspring, which is not supported by scientific evidence. Punctuated equilibrium is a theory about the pace of evolution and does not involve the specific mechanism of genetic alteration. Vicariance refers to the splitting of a population by a physical barrier, resulting in the divergence of two groups.

Question 3

Since life arose on Earth, ________ major extinctions have occurred.

Accepted Answer

The correct answer is six. The most well-known of these six extinctions is the one that happened about 65 million years ago, which killed off the dinosaurs.

Question 4

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

Accepted Answer

All the options listed (habitat loss, introduction of non-native species, pollution, and climate change) are considered significant anthropogenic threats to biodiversity.

Question 5

A monocultural agriculture community is ________ vulnerable to disturbance than an area with high biodiversity.

Accepted Answer

A monocultural agriculture community is composed of only one species of crop, making it more susceptible to diseases or pests that specifically target that species. A high biodiversity area, on the other hand, has multiple species of plants and animals, which provides a buffer against disturbances because if one species is affected, others still survive. Thus, monocultural agriculture communities are more vulnerable to disturbance.

Question 6

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

Accepted Answer

Insects have the highest number of known species among the options listed, with estimates of over a million described species, far surpassing plants, chordates, and bacteria.

Question 7

Continental drift separating a once continuous population is an example of

Accepted Answer

Vicariance refers to the separation of a once continuous population due to a physical barrier, such as continental drift. This can lead to divergence and speciation of the separated populations. Lamarckian evolution refers to the now discredited theory of inheritance of acquired traits, punctuated equilibrium is a model of evolution that suggests long periods of stability punctuated by sudden bursts of speciation, and mutation refers to changes in the genetic material of an organism.

Question 8

Which of the following is the correct order of lake succession, from lowest to highest nutrient levels?

Accepted Answer

Lake succession typically follows a pattern from oligotrophic (low nutrient levels) to mesotrophic (moderate nutrient levels) to eutrophic (high nutrient levels).

Question 9

Increased foliage cover in parts of Australia has been attributed to which of the following climate change related phenomena.?

Accepted Answer

The CO₂ fertilization effect refers to the increase in photosynthesis and growth rates of plants in response to elevated levels of atmospheric carbon dioxide. This phenomenon is a well-documented consequence of climate change and has been linked to increased foliage cover in parts of Australia.

Question 10

Human caused eutrophication is known as

Accepted Answer

Cultural eutrophication refers to the process where human activities such as agricultural runoff, sewage discharge, and industrial waste release excessive amounts of nutrients (e.g. nitrogen, phosphorus) into aquatic ecosystems, leading to an increase in algal blooms and a decline in water quality.

Question 11

In which portion of a lake would oligotrophic conditions most likely occur?

Accepted Answer

Oligotrophic conditions refer to low nutrient concentrations and high oxygen levels. These conditions are most likely to occur in deep water where there is limited light and little mixing with surface waters. Shallow areas, such as along the shore and in bays, are more likely to have higher nutrient concentrations and lower oxygen levels due to higher levels of organic matter production and decomposition. Areas with high nutrient inputs, such as near agricultural or urban areas, are also likely to have higher nutrient concentrations and lower oxygen levels.

Question 12

Studies have shown that ________ biodiversity in an ecosystem leads to ________ long-term stability and productivity.

Accepted Answer

Greater biodiversity means there are more species in an ecosystem to provide various services such as nutrient cycling, pollination, and pest control, leading to a more stable and productive ecosystem in the long term.

Question 13

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

Accepted Answer

The term "pioneer community" refers to the first group of species to colonize a disturbed or damaged ecosystem. A sere refers to a sequence of stages that an ecosystem goes through during ecological succession, which includes the pioneer community. Successor and establishment are not specific terms used in ecological succession.

Question 14

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

Ecological succession is the process that occurs when a disturbance results in the loss of most or all of the species in a community. Over time, new species will move in and replace the old ones, leading to changes in the community's species composition. Rejuvenation refers to the restoration of an ecosystem to a previous state, while mass extinction is the loss of a large percentage of species across the entire Earth. Patch dynamics refers to the spatial and temporal changes in species distribution within a landscape, but not necessarily the result of a disturbance that eliminates all species.

Question 15

The ability of an ecosystem to recover quickly from a disturbance and return to its original state is known as

Accepted Answer

Resilience refers to the ability of an ecosystem to bounce back and recover from a disturbance, such as a natural disaster or human intervention. It involves returning to its original state or adapting to a new state while maintaining essential function and overall structure. Vicariance refers to the geographical separation of populations that were once connected. Punctuated equilibrium is a theory in evolutionary biology that explains the sudden changes in the development of a species. Succession refers to the process of change in the species composition of an ecosystem over time.

Question 16

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

The notion described is that of natural selection, which is one of the core principles of evolutionary theory. Lamarckianism, punctuated equilibrium, and gradualism are all different concepts related to evolution, but they do not specifically refer to the process of traits being passed along based on their ability to help a species survive and reproduce.

Question 17

Approximately what percentage of plant and animal species have been classified overall.

Accepted Answer

Current estimates suggest that only about 13% of all plant and animal species have been classified and named. This means that there is still much to be discovered and documented in the world of biodiversity.

Question 18

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

Accepted Answer

The theory of evolution, proposed by Charles Darwin and Alfred Russel Wallace, explains the origin of Earth's biological diversity through the process of natural selection. This theory states that over time, genetic variations within populations can lead to the formation of new species that are better adapted to their environment, leading to biological diversity.

Question 19

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

Secondary succession occurs when a disturbance, such as a forest fire, leaves the soil and some remnants of the previous community intact. In this case, the vegetation would regenerate from the remaining seeds, roots, and buds, resulting in a new community of species gradually replacing the old ones. Primary succession, on the other hand, occurs in areas where no soil or biotic remnants remain, such as on a completely bare rock or where a glacier retreats, and requires the formation of soil from scratch. Tertiary and quaternary succession are not recognized ecological terms.

Question 20

Which of the following is not a measure of biological diversity?

Accepted Answer

All three options, species diversity, genetic diversity, and ecosystem diversity are measures of biological diversity. Therefore, D is not a correct answer.

Quiz 19: Ecosystem Essentials