MCQs Based On Environment – (52)

Correct Option: 3. Variation in genes within a species
Explanation: Genetic diversity refers to the differences in the DNA composition among individuals within the same species. These variations result in different traits such as size, color, resistance to diseases, and adaptability to environmental changes. High genetic diversity helps species survive natural selection and environmental stress. For example, the variety of colors in butterflies or the different types of roses arises due to genetic diversity. Without it, populations would be more vulnerable to extinction from diseases or environmental changes.

Correct Option: 4. Botanical garden
Explanation: Ex-situ conservation is the process of protecting an endangered species of plant or animal outside its natural habitat. Botanical gardens grow and maintain a variety of plant species in a controlled environment, making them an example of ex-situ conservation. These facilities are important for research, education, and conservation of rare and endangered species. In contrast, national parks and wildlife sanctuaries are examples of in-situ conservation, which focuses on protecting species in their natural habitats.

Correct Option: 2. Number of different species in an area
Explanation: Species richness is a quantitative measure of biodiversity that refers to the total number of different species present in a particular ecosystem or region, regardless of their population size. It provides a simple way to understand biodiversity. A forest with 100 species is considered richer than one with only 50, even if the individual count is higher in the latter. It does not consider the abundance or distribution, just the count of distinct species.

Correct Option: 2. IUCN
Explanation: The International Union for Conservation of Nature (IUCN) maintains the Red Data Book, also known as the IUCN Red List. It is the most comprehensive global source of information on the conservation status of animal, plant, and fungi species. The book categorizes species into different levels of threat such as Critically Endangered, Endangered, Vulnerable, etc., based on scientific assessments. It serves as a critical tool for conservation planning and policy-making worldwide.

Correct Option: 1. Elephant
Explanation: A keystone species is one whose presence and role in an ecosystem have a disproportionate effect on the other species and the environment. Elephants are considered keystone species because they shape their habitats by uprooting trees, creating clearings, and forming waterholes — actions that influence the survival of other plant and animal species. If keystone species are removed, it leads to significant changes in the ecosystem, often resulting in collapse or degradation.