Here are 25 multiple-choice questions on Biodiversity (General Issues) tailored for the JKSSB Forester Exam and similar competitive exams, with answers and explanations:
Biodiversity (General Issues)
Q1. What is the fundamental definition of biodiversity?
(a) The variety of plants in a specific region.
(b) The number of different species in a given area.
(c) The variability among living organisms from all sources including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part.
(d) The total number of genes present in a single organism.
Answer: (c)
Explanation: Biodiversity encompasses the variability of life at all levels, from genes to ecosystems, representing the full scope of life on Earth.
Q2. Which of the following is NOT a level of biodiversity?
(a) Genetic diversity
(b) Species diversity
(c) Economic diversity
(d) Ecosystem diversity
Answer: (c)
Explanation: The three main levels of biodiversity are genetic diversity (within a species), species diversity (between species), and ecosystem diversity (within and between ecosystems). Economic diversity refers to economic aspects, not a biological level of diversity.
Q3. What does ‘species diversity’ refer to?
(a) The total number of individuals in a population.
(b) The variety of genes within a single species.
(c) The number of different species in a community or area.
(d) The richness of habitats in a region.
Answer: (c)
Explanation: Species diversity is often measured by the number of different species (richness) and the relative abundance of each species (evenness) in a given area.
Q4. Which term describes the variation in genes within a single species?
(a) Ecological diversity
(b) Genetic diversity
(c) Functional diversity
(d) Structural diversity
Answer: (b)
Explanation: Genetic diversity refers to the variation in genetic characteristics within a species, essential for its adaptation and survival.
Q5. An area with a high number of different ecosystems (e.g., forests, grasslands, rivers) demonstrates high _____.
(a) species diversity
(b) genetic diversity
(c) ecosystem diversity
(d) cultural diversity
Answer: (c)
Explanation: Ecosystem diversity refers to the variety of different habitats, communities, and ecological processes within an environment.
Q6. What is a ‘biodiversity hotspot’?
(a) An area with a large number of endemic species and experiencing significant habitat loss.
(b) A region where a new species has recently been discovered.
(c) An area with exceptionally high climate temperatures.
(d) A location known for its successful conservation efforts.
Answer: (a)
Explanation: Biodiversity hotspots are biogeographic regions that are both significant reservoirs of biodiversity and are threatened with destruction. They must contain at least 1,500 species of vascular plants as endemics and have lost at least 70% of its primary vegetation.
Q7. Which major factor is considered the most significant threat to biodiversity today?
(a) Natural disasters
(b) Pollution
(c) Habitat loss and fragmentation
(d) Overpopulation by humans
Answer: (c)
Explanation: Habitat loss and fragmentation due to human activities like deforestation, agriculture, and urbanization are widely recognized as the primary drivers of biodiversity decline.
Q8. ‘Endemic species’ are those that are:
(a) Found only in zoos.
(b) Found exclusively in a particular geographical region.
(c) Able to adapt to any environment.
(d) Migratory birds traveling long distances.
Answer: (b)
Explanation: An endemic species is one that lives only in one specific geographical area and is not found anywhere else naturally.
Q9. The introduction of non-native species (also called exotic or alien species) into an ecosystem is known as:
(a) Speciation
(b) Bioaugmentation
(c) Biological invasion
(d) Niche partitioning
Answer: (c)
Explanation: Biological invasion occurs when non-native species are introduced to an ecosystem, often outcompeting native species and disrupting the ecological balance.
Q10. Which of the following is an example of an ‘in-situ’ conservation method?
(a) Botanical gardens
(b) Seed banks
(c) National Parks
(d) Gene banks
Answer: (c)
Explanation: In-situ conservation involves protecting species in their natural habitats, such as in National Parks, Wildlife Sanctuaries, and Biosphere Reserves. Botanical gardens, seed banks, and gene banks are examples of ex-situ conservation.
Q11. ‘Ex-situ’ conservation refers to:
(a) Protecting species in their natural environment.
(b) Protecting species outside their natural habitat.
(c) Restoring damaged ecosystems.
(d) Managing human-wildlife conflict.
Answer: (b)
Explanation: Ex-situ conservation means protecting species outside of their natural habitat, such as in zoos, botanical gardens, seed banks, and gene banks.
Q12. What is the primary purpose of a ‘seed bank’?
(a) To store seeds for agricultural use.
(b) To preserve genetic diversity of plant species.
(c) To conduct experiments on plant growth.
(d) To germinate seeds for reforestation.
Answer: (b)
Explanation: Seed banks are a crucial ex-situ conservation tool, designed to store seeds for long periods to preserve the genetic diversity of various plant species, especially those at risk.
Q13. The Convention on Biological Diversity (CBD) is an international treaty aimed at:
(a) Regulating international trade in endangered species.
(b) Conserving biodiversity, sustainable use of its components, and fair and equitable sharing of benefits arising from genetic resources.
(c) Preventing industrial pollution.
(d) Managing climate change impacts.
Answer: (b)
Explanation: The CBD has three main goals: the conservation of biological diversity; the sustainable use of its components; and the fair and equitable sharing of benefits arising from the utilization of genetic resources.
Q14. What does ‘extinction’ mean in the context of species?
(a) A species population decreasing by 50%.
(b) A species becoming rare in its habitat.
(c) The complete disappearance of a species from Earth.
(d) A species losing its ability to reproduce.
Answer: (c)
Explanation: Extinction is the complete disappearance of a species when there are no more living individuals left on the planet.
Q15. The term ‘keystone species’ refers to a species that:
(a) Is the largest predator in an ecosystem.
(b) Plays a crucial role in maintaining the structure and function of an ecosystem.
(c) Is the most numerous species in its habitat.
(d) Is the first species to colonize a new habitat.
Answer: (b)
Explanation: A keystone species is one whose presence is essential for the structure and function of an ecosystem; its removal would lead to significant changes or even collapse of the ecosystem.
Q16. What is ‘bioaccumulation’?
(a) The increase in concentration of a substance, such as a pesticide, in an organism over time.
(b) The process of organisms adapting to their environment.
(c) The growth of a population in a specific area.
(d) The breakdown of organic matter by microorganisms.
Answer: (a)
Explanation: Bioaccumulation is the gradual accumulation of substances, such as pesticides or other chemicals, in an organism. Biomagnification is the increase in concentration of pollutant as it moves up the food chain.
Q17. Which of the following is associated with ‘biomagnification’?
(a) Decreased concentration of toxins at higher trophic levels.
(b) Increased concentration of toxins at higher trophic levels.
(c) The ability of an organism to self-regulate its toxicity.
(d) The rapid dispersal of pollutants in an environment.
Answer: (b)
Explanation: Biomagnification is the process where the concentration of a toxin (like DDT or mercury) increases progressively as it moves up the food chain from lower to higher trophic levels.
Q18. The clearing of forests for other land uses is primarily known as:
(a) Afforestation
(b) Reforestation
(c) Deforestation
(d) Desertification
Answer: (c)
Explanation: Deforestation is the removal of a forest or stand of trees from land which is then converted to non-forest use.
Q19. What is the main objective of creating ‘Biosphere Reserves’?
(a) To promote tourism in natural areas.
(b) To protect only endangered animal species.
(c) To conserve biodiversity and promote sustainable development, often including human populations.
(d) To establish new agricultural lands.
Answer: (c)
Explanation: Biosphere Reserves are areas designated to reconcile the conservation of biological and cultural diversity and economic and social development through partnerships between people and nature.
Q20. Which international treaty aims to control the international trade of endangered species?
(a) Convention on Biological Diversity (CBD)
(b) Ramsar Convention
(c) Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)
(d) Kyoto Protocol
Answer: (c)
Explanation: CITES is a multilateral treaty to protect endangered plants and animals by regulating or banning international trade in their specimens.
Q21. ‘Ecological footprint’ is a measure of:
(a) The impact of an organism on its environment.
(b) The total land area required to support human activities.
(c) The number of endemic species in a region.
(d) The rate of natural resource consumption.
Answer: (b)
Explanation: The ecological footprint measures the amount of biologically productive land and sea area required to provide the resources a human population consumes, and to absorb its wastes.
Q22. What role do fungi and bacteria primarily play in an ecosystem?
(a) Producers
(b) Primary consumers
(c) Decomposers
(d) Apex predators
Answer: (c)
Explanation: Fungi and bacteria are vital decomposers, breaking down dead organic matter and returning nutrients to the soil, which are then used by producers.
Q23. The depletion of the ozone layer is linked to:
(a) Increased biodiversity.
(b) Global warming.
(c) Harmful ultraviolet (UV) radiation reaching Earth’s surface.
(d) Acid rain.
Answer: (c)
Explanation: The ozone layer absorbs most of the Sun’s harmful ultraviolet (UV) radiation. Depletion of this layer leads to more UV radiation reaching Earth, which can harm living organisms.
Q24. Which of the following is a direct ‘ecosystem service’?
(a) Economic revenue from logging.
(b) Cultural value of a landscape.
(c) Pollination of crops by insects.
(d) Research opportunities in a forest.
Answer: (c)
Explanation: Ecosystem services are the many and varied benefits that humans freely gain from the natural environment and from properly-functioning ecosystems. Pollination by insects is a direct service that supports agriculture.
Q25. The term ‘conservation’ in the context of biodiversity generally refers to:
(a) Maximizing resource extraction for economic gain.
(b) Protecting, preserving, and managing natural resources and ecosystems.
(c) Converting natural areas into agricultural land.
(d) Introducing new species to enhance existing ecosystems.
Answer: (b)
Explanation: Conservation involves the careful management and protection of natural resources and habitats to prevent their exploitation, destruction, or neglect, thereby maintaining biodiversity for present and future generations.
