IB Biology Quiz: Apply Conservation Of Biodiversity
19 questions · exam conditions
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Apply Conservation Of BiodiversityQuestion 1 of 19

Two protected forest reserves are separated by several kilometers of farmland. Genetic analysis of a large mammal population reveals that the animals in each reserve are becoming increasingly inbred. To address this, a plan is proposed to purchase and reforest a strip of land connecting the reserves.

What is the primary ecological justification for establishing this wildlife corridor?

To increase the total area of protected habitat available for the mammal population to expand its numbers.
To facilitate gene flow between the two isolated populations, thereby increasing genetic diversity.
To prevent the spread of infectious diseases from one reserve population to the other.
To provide a new and unexploited source of food for the mammals within the corridor itself.
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IB Biology Quiz

IB Biology Quiz: Apply Conservation Of Biodiversity

Practice Apply Conservation Of Biodiversity in IB Biology with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Apply Conservation Of Biodiversity, giving you a quick way to practice the rules, question types, and explanations that matter most for IB Biology.

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Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

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Question 1

Two protected forest reserves are separated by several kilometers of farmland. Genetic analysis of a large mammal population reveals that the animals in each reserve are becoming increasingly inbred. To address this, a plan is proposed to purchase and reforest a strip of land connecting the reserves.

What is the primary ecological justification for establishing this wildlife corridor?

  1. To increase the total area of protected habitat available for the mammal population to expand its numbers.
  2. To facilitate gene flow between the two isolated populations, thereby increasing genetic diversity. (correct answer)
  3. To prevent the spread of infectious diseases from one reserve population to the other.
  4. To provide a new and unexploited source of food for the mammals within the corridor itself.
Explanation: The primary purpose of a wildlife corridor is to connect fragmented populations, allowing individuals to move between them. This movement facilitates gene flow, which counteracts the negative effects of inbreeding and genetic drift that occur in small, isolated populations. While it does increase total habitat area (A) and may provide food (D), its main function is connectivity. Corridors can sometimes facilitate disease spread (C), making it a potential risk, not a justification.

Question 2

An invasive plant species is rapidly spreading through a national park, outcompeting native flora. One proposed management strategy is the introduction of a specialized insect herbivore from the plant's native range, a method known as biological control.

What is the most significant potential ecological risk associated with this biological control strategy?

  1. The introduced insect may fail to establish a viable population due to predation or climate mismatch.
  2. The insect could eventually consume the entire population of the invasive plant, leaving itself with no food source.
  3. The introduced insect might adapt to feed on native plant species, becoming an invasive pest itself. (correct answer)
  4. The cost of screening and releasing the biological control agent could exceed the cost of manual removal of the plant.
Explanation: The greatest risk in biological control is that the control agent may have unintended, non-target effects. If the insect herbivore begins to feed on native plants, it could cause significant harm to the ecosystem it was meant to protect. While failure to establish (A), over-effectiveness (B), and cost (D) are all valid concerns, the risk of creating a new invasive species with widespread ecological damage is the most significant.

Question 3

A large, square-shaped nature reserve is established. Years later, a major highway is built that bisects the reserve, though the total protected land area remains unchanged. The highway is fenced to reduce roadkill.

From an ecological perspective, how does the construction of the highway most significantly impact the biodiversity within the reserve?

  1. It increases the proportion of the reserve that functions as 'edge habitat', which can be detrimental to interior-specialist species. (correct answer)
  2. It makes the reserve more accessible to tourists, increasing revenue for conservation management.
  3. It divides the reserve into two smaller, more easily managed administrative units for park rangers.
  4. It creates a physical barrier that completely prevents the exchange of genetic material between the two sides.
Explanation: Building a road through a habitat creates 'edges' where the forest meets the cleared area. This edge habitat has different environmental conditions (e.g., more light, wind, different temperature) than the interior. This increase in the ratio of edge to interior habitat is known as the edge effect and can harm species adapted to the stable conditions of the forest interior. While it is a barrier (D), some species might cross, so 'completely prevents' is too strong; the edge effect is a more pervasive impact. Accessibility (B) and management (C) are not ecological impacts on biodiversity.

Question 4

A persistent, non-biodegradable pesticide used in agriculture is found to have entered a lake's food web. The food web consists of phytoplankton, zooplankton that eat phytoplankton, small fish that eat zooplankton, large fish that eat small fish, and ospreys (birds) that eat large fish.

In which of the following would the concentration of the pesticide be expected to be the highest due to biomagnification?

  1. The lake water.
  2. The tissues of phytoplankton.
  3. The tissues of small fish.
  4. The tissues of ospreys. (correct answer)
Explanation: Biomagnification (or bioaccumulation) is the process by which the concentration of a persistent toxin increases at successively higher levels in a food chain. The pesticide is absorbed by phytoplankton, concentrated in zooplankton that eat them, further concentrated in small fish, then large fish, and finally reaches its highest concentration in the apex predator, the osprey. Therefore, the osprey's tissues will have the highest concentration.

Question 5

A debate occurs over the best strategy to conserve a large coral reef. One option is to designate it as a no-take marine protected area (in situ). The other is to collect diverse coral specimens for preservation and propagation in large, specialized aquarium facilities (ex situ).

What is a key advantage of the in situ approach for conserving the biodiversity of the entire coral reef ecosystem?

  1. It allows for easier genetic screening of corals to identify disease-resistant genotypes for future restoration.
  2. It preserves the complex web of ecological interactions among thousands of interdependent species. (correct answer)
  3. It completely protects the coral from global threats such as ocean acidification and rising sea temperatures.
  4. It guarantees the survival of all coral species within the area, even in the event of a severe bleaching event.
Explanation: The most significant advantage of in situ conservation is that it protects not just individual species, but the entire ecosystem, including the countless interactions between them (predation, symbiosis, competition). These interactions cannot be replicated in an artificial ex situ environment. Genetic screening (A) might be easier ex situ. An in situ reserve offers no protection from global threats like warming (C) and cannot guarantee survival against severe events like bleaching (D).

Question 6

A species of alpine flower is protected in a national park located at the southern limit of its natural range. Climate change models for the next 50 years predict that this region will become significantly warmer and drier.

What is the most significant long-term conservation challenge for this particular plant population, given the park's fixed boundaries?

  1. The park's static location may prevent the species' natural poleward migration in response to the changing climate. (correct answer)
  2. Increased temperatures will directly lead to a higher rate of mutation in the flower's pollen grains.
  3. Warmer weather will attract more tourists to the park, leading to increased trampling of the flowers.
  4. The fixed boundaries of the park will make it more difficult for rangers to patrol for illegal plant collectors.
Explanation: As the climate warms, species' suitable habitats tend to shift towards the poles or to higher altitudes. A protected area with fixed boundaries can become a 'climate trap'. The flower population may be unable to migrate to cooler, more suitable habitats further north because the park does not extend there, leading to its local extinction. While increased tourism (C) is a potential issue, the fundamental ecological problem is the mismatch between a static reserve and a dynamic climate.

Question 7

A conservation agency must decide how to allocate limited funds. One option is to protect a 'flagship species,' a charismatic panda. The other is to protect a 'keystone species,' a sea otter that maintains the health of kelp forests by controlling sea urchin populations.

From a purely ecological standpoint, what is the strongest argument for prioritizing the conservation of the sea otter?

  1. Protecting the sea otter will indirectly conserve the kelp forest ecosystem and its high associated biodiversity. (correct answer)
  2. The panda is more expensive to maintain in captivity, making the sea otter a more cost-effective choice.
  3. The sea otter has a faster reproductive rate, meaning its population will recover more quickly with protection.
  4. The panda's popularity can generate more public donations and awareness for conservation in general.
Explanation: A keystone species has a disproportionately large effect on its environment relative to its abundance. The sea otter's predation on sea urchins prevents urchins from overgrazing kelp, thereby preserving the entire kelp forest habitat for many other species. Therefore, protecting the sea otter provides a high degree of ecological leverage. While the panda's flagship status is good for fundraising (D), the ecological argument for the keystone species is its critical role in maintaining ecosystem structure and function.

Question 8

The last 30 individuals of a rare reptile species have been brought into a zoo to form a captive breeding program. All individuals are healthy and are expected to reproduce successfully.

What is the most significant long-term genetic challenge that this conservation program will face?

  1. The difficulty in replicating the species' natural diet, which could affect reproductive success.
  2. The high susceptibility of the entire population to a single disease outbreak due to their close proximity.
  3. The inevitable loss of genetic diversity and increased inbreeding due to the small founding population size. (correct answer)
  4. The risk of the reptiles hybridizing with a closely related species housed in the same zoological facility.
Explanation: Starting a population from a very small number of individuals creates a 'genetic bottleneck.' Even if the population size increases, the genetic diversity is limited to the alleles present in the original 30 founders. This leads to increased inbreeding and reduced ability for the species to adapt to future environmental changes. While diet (A), disease (B), and hybridization (D) are practical management challenges, the fundamental genetic bottleneck is the most significant long-term threat to the species' viability.

Question 9

[HL] The Convention on Biological Diversity (CBD) is a multilateral treaty with three main goals: the conservation of biodiversity, the sustainable use of its components, and the fair sharing of benefits arising from genetic resources.

[HL] What is a primary limitation in the effectiveness of the Convention on Biological Diversity as an instrument for global conservation?

  1. The treaty focuses only on terrestrial ecosystems and does not include provisions for marine biodiversity.
  2. The provisions of the treaty are not legally binding, and enforcement relies on the will of individual nations. (correct answer)
  3. Membership is limited to developing countries, excluding many nations with high technological capacity.
  4. The treaty's goals are determined by a council of corporations and not by scientific advisory bodies.
Explanation: A key challenge for the CBD is that it is a framework convention. While nations agree to the overall goals, the specific actions, targets, and laws are developed and enforced at the national level. The treaty itself does not have a strong international enforcement mechanism, making its implementation dependent on the political will and capacity of each signatory country. The other statements are incorrect: the CBD covers all ecosystems (A), has near-universal membership (C), and is guided by scientific bodies (D).

Question 10

A seed bank aims to preserve the genetic diversity of crop plants. It successfully stores seeds from hundreds of varieties of a particular species of bean, collected from farms all over the world.

While this ex situ strategy effectively conserves genetic information, which crucial aspect of the beans' biodiversity is not preserved in the seed bank?

  1. The co-evolutionary relationship between the bean varieties and their specific local pollinators and soil microbes. (correct answer)
  2. The unique DNA sequences that code for important traits like drought resistance and disease tolerance.
  3. The ability of the seeds to germinate and produce viable adult plants under controlled conditions.
  4. The economic value of the beans as a food source for human populations in different regions.
Explanation: Seed banks preserve the genetic material of the plants themselves but remove them from their ecological context. This means the ongoing, dynamic relationships with other organisms—such as co-evolution with pollinators, symbiotic relationships with nitrogen-fixing bacteria, and interactions with pests and diseases—are lost. The DNA sequences (B) are precisely what is being preserved. Germination ability (C) is regularly tested and maintained. The potential economic value (D) is a key reason for preservation.

Question 11

A conservation plan for an endangered plant species involves collecting seeds. The species exists in several small populations that are geographically isolated from one another in different mountain valleys.

What is the primary genetic justification for collecting seeds from all the different populations rather than a large number of seeds from just one population?

  1. To minimize the travel costs and logistical complexity associated with the seed collection process.
  2. To ensure that if a disease eliminates one population, seeds from the others will still be preserved.
  3. To capture the maximum amount of genetic diversity, as isolated populations are likely to have unique alleles. (correct answer)
  4. To prevent the over-collection of seeds from a single population, which could harm its reproductive capacity.
Explanation: Geographically isolated populations often evolve slight genetic differences (unique alleles) due to local adaptation and genetic drift. To preserve the full genetic diversity of the species, it is crucial to sample from across its entire range. This broad genetic base is vital for the species' potential to adapt to future environmental changes. While preventing over-collection (D) and having backups (B) are valid points, the core goal is to capture the full spectrum of genetic diversity.

Question 12

Fisheries biologists report that a commercially important fish stock is experiencing overexploitation. The regulatory body is considering new quotas to address the issue.

What is the precise biological meaning of 'overexploitation' in this context?

  1. The rate of harvest is exceeding the rate at which the population can replenish itself through reproduction. (correct answer)
  2. The market price of the fish has dropped to a point where fishing is no longer economically profitable.
  3. The fishing fleet is using methods that are banned by international maritime law for this region.
  4. The total number of fish being caught exceeds the legal quota set for the previous fishing season.
Explanation: Overexploitation is a biological concept referring to the harvesting of a renewable resource to the point of diminishing returns. In population dynamics, this means the mortality rate from harvesting is greater than the birth rate, leading to a decline in the population's biomass. Exceeding a legal quota (D) is a legal issue that may or may not correspond to biological overexploitation. Profitability (B) is an economic issue, and illegal methods (C) is a legal one. The core biological issue is the population's ability to sustain itself.

Question 13

[HL] Ecologists are monitoring the recovery of a river downstream from a former industrial site. They are using a biotic index based on the presence and abundance of different aquatic invertebrate species, which vary in their tolerance to pollution.

[HL] If the river is recovering and water quality is improving, what change would be expected in the invertebrate community?

  1. An overall decrease in the total number of individual invertebrates but an increase in the total biomass.
  2. An increase in the populations of pollution-tolerant species like sludge worms and a decrease in sensitive species.
  3. A shift in community composition towards a higher proportion of pollution-sensitive species like stonefly larvae. (correct answer)
  4. A stabilization of the community where the relative abundance of all species remains constant over time.
Explanation: Biotic indices work on the principle that different species have different pollution tolerances. In polluted water, only tolerant species (like sludge worms) can survive. As water quality improves, sensitive species (like stonefly and mayfly larvae), which cannot survive in polluted conditions, can recolonize. Therefore, a sign of recovery is an increase in the diversity and abundance of these pollution-sensitive indicator species.

Question 14

[HL] A rare species of timber tree is listed under Appendix I of the Convention on International Trade in Endangered Species (CITES).

[HL] What is the most direct consequence of this Appendix I listing for international commerce?

  1. It mandates that all remaining wild populations of the tree must be enclosed within national parks.
  2. It funds research into developing sustainable plantation methods for growing the tree commercially.
  3. It prohibits all international commercial trade in the timber and products derived from this tree. (correct answer)
  4. It requires that an environmental impact assessment be conducted before any of the timber can be harvested.
Explanation: CITES is a treaty that regulates international trade in threatened species. Appendix I includes species threatened with extinction. For these species, international commercial trade in wild-caught specimens (or their parts, like timber) is banned. Trade may be permitted in exceptional, non-commercial circumstances (e.g., for scientific research), but the primary consequence is a ban on commercial trade. CITES does not mandate habitat protection (A), fund research (B), or regulate domestic harvesting practices (D); it specifically governs international trade.

Question 15

A plant species is discovered that exists only on the slopes of a single, volcanically active island. The total population is estimated to be fewer than 200 individuals. Conservation biologists are debating the most effective strategy to prevent its extinction.

Given the specific circumstances of this plant species, why might an ex situ conservation approach, such as establishing a population in a botanical garden, be prioritized over a purely in situ approach?

  1. An ex situ approach is significantly less expensive than managing a remote island habitat and monitoring its population.
  2. It mitigates the high risk of a single catastrophic geological event wiping out the entire wild population. (correct answer)
  3. The plant will experience less competition from other species in a cultivated environment, allowing it to evolve more rapidly.
  4. Studying the plant's reproductive biology is only possible under controlled ex situ conditions, which is essential for conservation.
Explanation: The primary justification for prioritizing ex situ conservation in this scenario is the extreme vulnerability of the entire species to a single, localized catastrophic event (a volcanic eruption). An off-site population acts as an insurance policy. While cost (A) is a factor, it's not the primary biological reason. Evolution is slower in controlled environments with reduced selective pressures (C). Reproductive biology can often be studied in situ, although ex situ may make it easier (D), but the immediate extinction risk is the overriding concern.

Question 16

A captive breeding and reintroduction program for a critically endangered bird has been running for ten years. The total population has increased from 50 to 500 individuals, and all released birds are tagged and monitored.

Which additional piece of information is most crucial for evaluating the long-term success and sustainability of this conservation program?

  1. The average annual cost of raising and releasing one bird from the program.
  2. The percentage of eggs laid in captivity that successfully hatch each year.
  3. Data showing that released birds are successfully reproducing in the wild without human support. (correct answer)
  4. The genetic diversity of the current captive population compared to the original 50 founders.
Explanation: The ultimate goal of a reintroduction program is to establish a self-sustaining wild population. While population size increase is a positive sign, the program is only truly successful if the released animals can survive and reproduce on their own. Cost (A), captive breeding success (B), and genetic diversity (D) are important metrics, but evidence of a self-sustaining wild population is the most critical indicator of long-term success.

Question 17

A plant species that was declared extinct in the wild has been successfully cultivated for years in a botanical garden. A program is now being designed to reintroduce it to its original native habitat.

Before attempting the reintroduction, what is the most critical ecological factor that must be assessed in the target habitat?

  1. Whether the original threat that caused the plant's extinction has been successfully identified and removed. (correct answer)
  2. The exact number of individual plants that are available for the initial reintroduction effort.
  3. The level of genetic diversity within the cultivated stock compared to historical specimens.
  4. The amount of media coverage and public support the reintroduction project is likely to receive.
Explanation: Reintroducing a species into an environment where the cause of its original decline (e.g., a specific disease, an invasive competitor, habitat destruction, pollution) still exists is highly likely to fail. Therefore, the most critical first step is to ensure that the original threats have been mitigated. While the number of plants (B), their genetic diversity (C), and public support (D) are all important logistical and long-term considerations, they are secondary to ensuring the habitat is actually suitable for survival.

Question 18

A project aims to reintroduce a top predator, the grey wolf (Canis lupus), to an ecosystem where it was hunted to extinction a century ago. The ecosystem is currently characterized by an overpopulation of herbivores like deer, which has led to overgrazing of vegetation.

What is a primary ecological objective of reintroducing this keystone species?

  1. To restore top-down trophic control, regulating herbivore populations and indirectly benefiting plant communities. (correct answer)
  2. To increase ecotourism revenue by providing opportunities for visitors to see a charismatic predator.
  3. To directly increase the population of the deer, which will serve as a stable food source for the wolves.
  4. To fulfill an ethical obligation to restore all species that were historically present in the ecosystem.
Explanation: As a keystone species and top predator, the wolf exerts top-down control on the food web. By preying on herbivores like deer, wolves can reduce their numbers and change their grazing behavior. This regulation of herbivores can lead to a 'trophic cascade,' allowing vegetation to recover, which in turn benefits many other species. Ecotourism (B) is an economic benefit, not an ecological objective. The wolf reintroduction would decrease, not increase, the deer population (C). The ethical argument (D) is a valid motivation but not the ecological mechanism or objective.

Question 19

[HL] A species of frog is moved from the 'Vulnerable' category to the 'Endangered' category on the IUCN Red List.

[HL] What does this reclassification most directly imply about the species?

  1. The species is now completely extinct in at least one country where it was formerly found.
  2. A new threat, such as a fungal disease, has been discovered to be affecting the frog population.
  3. Quantitative analysis of population size, trend, and range indicates a higher risk of extinction. (correct answer)
  4. The species is now automatically protected under international law by the CITES treaty.
Explanation: The IUCN Red List categories are based on a rigorous, quantitative assessment of extinction risk using criteria such as population size, rate of decline, geographic range, and degree of fragmentation. Moving from 'Vulnerable' to 'Endangered' signifies that the species has crossed a threshold indicating a higher probability of extinction in the wild. While a new threat (B) could be the cause, the reclassification itself is a statement about the assessed level of risk. Local extinction (A) is one possible factor, but not the definition of the change. IUCN status informs CITES listings (D), but they are separate and the process is not automatic.