Biodiversity and Conservation Important Questions

CBSE Class 12 Biology Biodiversity and Conservation Important Questions have been provided in this article along with a detailed explanation as per the latest CBSE Board Curriculum. The article covers all the important topics from the chapter such as Biodiversity, Patterns of Biodiversity, Genetic Diversity, Species Diversity, Ecological Diversity, Loss of Biodiversity, and Biodiversity Conservation.

Biodiversity is a term that represents the combined diversity of biological organizations at all levels. Some of the important diversities include Genetic Diversity, species diversity, and biological diversity. Biodiversity is very essential for the survival of the earth and its creatures and its conservation has now become a major environmental issue over the past few decades.

Biodiversity

Read More: Our Environment

---

Very Short Answer Questions (1 Mark Questions)

Ques. Define Biodiversity. [CBSE Delhi 2018]

Ans. Biodiversity is the term used to describe the combined diversity at all levels of biological organization. It also refers to a total collection of genes, species, and ecosystem, i.e. an ocean or a forest.

Ques. What is the difference between Species Diversity and Ecological Diversity?

Ans. The diversity at the species level is known as species diversity. It represents the distribution of a species in an area whereas, Ecological diversity refers to the diversity at the ecological level.

Ques. What is Genetic diversity? Give Example.

Ans. When a single species develop diversity due to diversities in the genes, then it is known as Genetic Diversity. There are more than 50,000 genetically different strains of rice presently in India.

Ques. Give characteristics of a stable community. [CBSE Delhi 2017]

Ans. Some of the major characteristics of a stable community are given below:

• Carrying capacity,
• Recycling of wastes,
• Density-related self-regulation 
• Feedback system.

Ques. What is ‘Frugivorous’?

Ans. Frugivorous refers to fruit-eating animals.

Read More: Carnivores and Herbivores

Ques. What is a biodiversity hotspot and why is it important?

Ans. Biodiversity Hotspot is a term for a biogeographic region that has a significant amount of biodiversity and is threatened by human habitats. A biodiversity hotspot is important to protect and conserve the ecosystem and maintain ecological balance globally.

Ques. Define ‘Gene pool’.

Ans. A Gene pool is the total of all the existing species of a single individual in a breeding population.

Ques. Define the following: [CBSE Outside Delhi 2012]

• Red Data Book
• Endemism
• Bioprospecting

Ans. The definitions are as follows: 

• Red Data Book: This is a book of collection of all the species at risk of extinction listed by IUCN.
• Endemism: It refers to the species that are unique and found only in some particular areas.
• Bioprospecting: It refers to the process of discovery and commercialization of new products from plant and animal species.

Ques. State a difference between endemic and exotic species.

Ans. Endemic species are restricted to only a particular geographical area whereas Exotic species are derived from another geographical area.

Ques. What are the two most biodiversity-rich zones in India?

Ans. The Western Ghats and the Eastern Himalayas are the two most biodiversity-rich zones in India.

Western Ghats (Biodiversity Hotspot)

Read More: Extinction

---

Short Answer Questions (2 Marks Questions)

Ques. Can the loss of one species lead to the loss of another? If yes then justify your answer with an example. [CBSE Delhi 2015]

Ans. Yes, in co-extinction, where the survival of one species is completely dependent on another, the loss of one species could lead to the loss of another. In co-extinction, the species are related to each other in an obligatory method. For example, if the host fish dies, the parasites will be dead too as parasites are the dependent species.

Ques. What accounts for greater diversity in Tropical and Subtropical regions as compared to temperate regions? [CBSE Outside Delhi 2016]

Ans. In tropical and subtropical areas, the temperature and various climatic conditions do not vary much. This leads to a longer time in evolution, hence a greater diversity. In temperate regions, unlike tropical areas, the climatic conditions are quite unpredictable and changes occur rigorously, resulting in a short period of evolution which accounts for lesser diversity.

Ques. Why are amphibians more susceptible to extinction?

Ans. These are some of the reasons for amphibians being more susceptible to extinction.

• Habitat fragmentation
• Habitat Destruction or Modification
• Large-scale climate change

Ques. List down the consequences of loss of biodiversity. [CBSE Delhi 2013]

Ans. Consequences of loss of biodiversity:

• This may lead to large variability in the ecosystem.
• Loss of biodiversity may lead to the extinction of species.
• Survival rates will rapidly decrease.
• The species under co-extinction will face huge extinction.
• Loss of biodiversity may lead to some natural calamities like floods.
• Loss of biodiversity will result in the difficult survival of human beings as man is dependent on food and animals for its survival.

Read More: Conservation of Plants & Animals

Ques. Why is Species diversity more in animals as compared to plants?

Ans. Animals possess a nervous system that is responsible for coordinating every activity. Receptors in animals help them receive environmental stimuli. They can receive an adaptive change that ensures the survival of animals, which is why animals have more diversity. Plants neither have a nervous system nor receptors to accept the adaptive changes; hence their survival rate is much lesser than animals in environmental conditions.

Ques. Differentiate between In-Situ and Ex-Situ conservations.

Ans. The difference between In-Situ and Ex-Situ conservations is as follows: 

Ques. What are the factors responsible for species extinction?

Ans. The factors responsible for species extinction are: 

• A decline in several species at a concerning rate.
• A modification or destruction in the natural habitat of species.
• Increasing activities of poachers.
• Over exploitation of natural resources.
• Concerning rate change of climatic conditions.
• Invasion of foreign species.

Endangered Species

Also Check:

---

Long Answer Questions (3 Marks Questions)

Ques. What is biodiversity? Explain different types of biodiversity. [CBSE Delhi 2018]

Ans. Biodiversity is the term used to describe the totality of all the genes and species at all levels in a biological organization. Biodiversity is important for the survival of the earth. It is the base of various ecosystems present on earth. Given below are the types of biodiversity:

• Genetic Biodiversity: the diversity in genes of a single species is known as genetic diversity. Species with more genetic diversities have greater survival rates against harsh conditions and the environment. Species with lesser genetic diversities are more prone to diseases and harsh natural environments.
• Species Biodiversity: The diversity of species within a geographical area is known as Species biodiversity. For example, the species diversity of amphibians is more in the Western Ghats as compared to the Eastern Ghats.
• Ecological Diversity: This represents the diversity at the ecosystem level. For example, In India, the deserts, coral reefs, alpine ecosystems, oceans, and forests have more ecological biodiversity than Norway.

Read More: MCQs on Biodiversity and Conservation

Ques. Explain Latitudinal Gradient. Give reasons for the lesser diversity in temperate regions as compared to tropical zones.

Ans. Latitude Gradient means that there is more amount of species diversity found near the equator. Moving away from the Equator (towards the poles) accounts for less species diversity. The equator region at latitude 23.05 c has more diversity than the temperate zones or poles.

There is lesser diversity in temperate regions as compared to tropical zones because

• Due to the glaciations in the past in temperate zones, the frequent changes in the environment led to a lesser development of species resulting in less species population.
• As compared to temperate zones, tropical zones have more predictable and constant climatic conditions that helped in survival and species development.
• There is no or minimum amount of solar radiation in tropical zones which accounts for a greater productivity rate.

Ques. Describe the relation between Species-richness and area. [CBSE Outside Delhi 2015]

Ans. Alexander Von Humboldt gave a relation between Species-richness and area. He observed that in an area, the species richness increased with the increase in the explored area but only up to a limit.

For several taxa, the relationship between species richness and area is considered to be a rectangular hyperbola. The relationship is linear and is given by:

log S = log C + Z log A

Where,

• S = Species Richness
• Z = Slope of the line (regression coefficient)
• A = area
• C=y-intercept

• The value of Z generally lies between 0.1 and 0.2.
• The value of Z for large areas such as the continent lies between 0.6 and 1.2.
• For frugivorous birds and animals, the Value of Z is found to be 1.15.

Ques. What are sacred groves? Are these areas helping us to conserve biodiversity? If yes, then give relevant points. [CBSE Outside Delhi 2016]

Ans. Sacred groves are the forest patches around the worship area that are highly preserved and protected by the tribal communities.

Scared groves are made around temples or religious areas and are ultimately preserved. In this region, all the animals and plants are given complete protection and care. For example, Khecheopalri Lake in Sikkim is protected by the tribal people, Aravalli hills in Rajasthan and the Western Ghats in Karnataka are some of the highly preserved Sacred Groves in India.

Role of Sacred Groves in preventing loss of Biodiversity: Sacred Groves, being highly religious areas are surrounded by the most degraded landscaped. These areas are usually undisturbed and all the species are given complete care and protection.

Read More: Ecology and Environment

---

Very Long Answer Questions (5 Marks Questions)

Ques. Mention the main causes of loss of diversity.

Ans. The Biological Diversity of the earth is decreasing rapidly. There are four major causes of the loss of diversity also known as The Evil Quartet.

1. Habitat Loss and Fragmentation: this is the main cause of loss of diversity. Fragmentation of crops and conversion to grassland for beef cattle has resulted in decreased species of plants and animals. Earlier, the rain forest were covering about 14% of the total land area of earth but now the area has reduced to only 6%. Cleaning up the forest for crops and cattle destroyed the natural habitat of migratory birds too.
2. Overexploitation: overexploitation of natural resources by human beings has resulted in a loss of biodiversity. Overuse of natural resources like water bodies, soil resources, and forest areas has led to the degradation of natural habitats. Human-caused pollution is the biggest reason for the degradation of biodiversity.
3. Invasion of Alien Species: When alien species knowingly or unknowingly are introduced to natural habitat, some of them become invasive and compete with the endangered indigenous species. For example, the introduction of African catfish for aquaculture purposes has led to the extinction of some indigenous species.
4. Co-extinction: this is a type of existence where one where species is completely dependent on the other for its survival. Co-extinction is a threat to our biodiversity as the extinction of a single species may lead to the extinction of a whole community.

Ques. What are the two main approaches to conserving biodiversity in India? Explain in detail.

Ans. India has been one of the most prestigious countries in terms of biodiversity. Now as the degrading factors are increasing, it is the need for an hour to protect Biodiversity. Here are the two approaches that are used in India to conserve Biodiversity in India.

Ex-Situ Biodiversity Conservation

In this type of conservation, species under threat are removed from their respective natural habitats and are placed in an artificial habitat under the care of humans.

• Botanical gardens, Zoological parks, and arboreta are some examples of Ex-situ conservation.
• Cryopreservation is another example of ex-situ conservation where materials are stored at an ultra-low temperature either by rapid or slow cooling.

In-Situ Biodiversity Conservation

In this approach of conservation, the endangered species are protected in their natural habitat either by cleaning the habitat or protecting it from poachers. It includes

• Biospheres Reserves: there are in total 425 biosphere reserves in the world. Hotspots have been made to conserve endangered species with utmost precision.
• National Parks and Wildlife Sanctuaries: India has 90 national parks and more than 440 wildlife sanctuaries.
• Sacred Forests: These are undistributed forests untouched by human beings and are used only for sacred purposes.

Periyar Wildlife Sanctuary

Read More: Difference Between Wildlife Sanctuary and National Park

Ques. How can we prevent the loss of diversity? Explain in detail. [CBSE Delhi 2013]

Ans. Loss of diversity can be prevented through various conservation techniques and management.

• Natural conservation of various plants and animals by keeping them protected in their respective habitats.
• By increasing the number of sacred forests, the loss of biodiversity can be prevented.
• A strict ban on hunting and poaching. There should be strict laws against illegal hunters and poachers.
• Limiting the use of natural resources. Avoiding the over-exploitation of natural resources.
• Strict laws should be made for visitors visiting forests or mountain areas.
• Conserving the natural habitats including breeding and feeding areas.
• By spreading awareness about the loss of biodiversity through campaigns and regular drives.