Biodiversity: Definition, Types and Significance

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Anjali Mishra Content Writer-SME

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Biodiversity refers to a variety of species on earth including the plants, animals, and microorganisms. Edward Wilson, a sociobiologist was the first to popularise the term ‘biodiversity’ in the year 1992. The term ‘biodiversity’ is derived from the two words- ‘bios' which means life and ‘diversity’ means differentiation or variation. The International Union for Conservation of Nature (IUCN) has recorded the total number of species to be greater than 1.5 million.

  • Biodiversity supports all the resources present in nature such as food, water, shelter, etc.
  • Several species already exist and more are yet to be discovered.
  • In India, known species is roughly 8.1% of the total, though India has only 2.4% land area.

What is Biodiversity? 

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Biodiversity, also known as biological diversity talks about a variety of life forms that exist on earth. Endangered or threatened species including plants, animals, fungi, viruses, humans, and invertebrates are included in a biodiversity. It has both economical and ecological significance as it provides us with food, shelter, medicines, clothings, etc. 

  • Genetic variation and evolution are the two driving factors responsible for increasing biodiversity & population. 
  • Habitat destruction, foreign invasion, and natural disasters are the three main causes of population decline in a biodiversity.
  • According to Centre of Biodiversity and Conservation, both humans and human cultural diversity are a part of this. 

Types of Biodiversity

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Biological diveristy refers to all species living in one area or ecosystem.Thus, there are three different levels of biodiversity which are discussed below in detail: 

  1. Genetic diversity
  2. Species diversity
  3. Ecological diversity

Types of biodiversity

Types of biodiversity

Genetic Diversity

The variation among genetic resources of an organism is known as genetic biodiversity. Populations that are diverse genetically can very well handle change.

  • For instance, if a population is striked by a disease increased levels of genetic diversity increase the chances that only a few members are affected by the disease.
  • Example of biodiversity is Rauwolfia vomitoria, a medicinal plant found in the Himalayas shows genetic variation in terms of potency and concentration of the chemical Reserpine.

Species Diversity

The variety of different species found in a specific area is known as species biodiversity. It also means the role a specie play in the community. 

  • For instance, a community is made up of several different species, but might have only one predator that chose only a specific prey.
  • For example, the Western Ghats in India have more amphibian species than the Eastern Ghats.

Ecological Diversity

The biodiversity found at the ecosystem level of a region is known as ecological biodiversity. For example, India with its vast deserts, thick rainforests, rich mangroves has higher ecological biodiversity than Norway.


Significance of Biodiversity

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The proper maintenance of biodiversity is essential for survival on Earth. An area rich in higher species is considered to be more stable than an area in deprivation. Moreover, we rely entirely on the environment to fulfill our needs to survive.

  • It provides ecological stability by providing various services required for the survival of human life.
  • Every species serves a specific function in an ecosystem. Some produce and decompose organic matter while others capture and store energy.
  • An abundant and diverse ecosystem is more productive and resilient to environmental stress like droughts, floods, landslides, etc.
  • Rich biodiversity provides economic value as it is a reservoir of various resources like cattle, fishes, forests, medicinal herbs, wood, crops, etc., all essential for the propagation of life on Earth.
  • Abundant and balanced biodiversity also provides ethical and aesthetic value by conserving the rich cultural heritage.
  • It also play a significant role in regulating climate, soil formation, decreasing pollution, etc.
  • They help in capturing, storing, utilizing, breaking organic materials, and fixing nitrogen.

Causes of Biodiversity Loss

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Biodiversity losses occur due to the destructive human activities and deteriorating climate crises. The top 10 biodiversity loss causes are metioned below:

  • Population explosion/overpopulation
  • Extensive mechanization/industrialization
  • Loss of habitat
  • Changes in climate
  • Urbanization
  • Deforestation
  • Pollution
  • Diseases
  • Erosion
  • Depletion

Consequence of Biodiversity loss

Following are some major consequences of loss of biodiversity: 

  • Plant production is declining
  • Reduced resistance to droughts, floods, landslides, etc leading to calamities
  • Many beneficial species have become extinct
  • The use of pesticides has increased leading to the increase in many serious diseases like cancer

Biodiversity Conservation

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Biodiversity conservation refers to the measures taken to preserve, protect, and uplift the biodiversity of flora and fauna so that renewable and non-renewable resources can be obtained for the sustenance of present and future generations.

The main goals of biodiversity conservation are:

  • Conservation of species
  • Management of ecosystems
  • Restoration of various ecological processes

Methods of Biodiversity Conservation

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There are primarily two methods of biodiversity conservation: In situ and Ex situ Conservation.

Methods of Biodiversity Convservation

Figure 2: The in-situ and ex-situ biodiversity conservation in India

In-situ Conservation

In-situ conservation of biodiversity is the preservation of various species of animals and plants in their natural environment or habitat. It includes national parks, sanctuaries, forests, reserves, etc.

Advantages of In-situ conservation

In-situ conservation of biodiversity has several advantages:

  • It is a cost-efficient way of biodiversity conservation
  • It ensures the conservation of a large number of species at the same time
  • The organisms don’t require to change their habitat

National Parks

National parks are the forest reserves that are managed by the government. Activities like grazing, farming, construction, cutting of trees, hunting, etc., are strictly prohibited in these areas for the conservation of different species of flora and fauna.

India has a total of 104 National Parks that are covering an area of 43,716 square kilometers. Eg. Jim Corbett National Park, Kanha National Park, Gir National Park, Kaziranga National Park, Sundarbans National Park, etc.

Wildlife Sanctuaries

Wildlife sanctuaries are the areas reserved specifically for the conservation of wild animals. Tourists are allowed in these areas. India has a total of 551 wildlife sanctuaries.

Eg. Periyar Wildlife Sanctuary in Kerala, Ghana Bird Sanctuary, Abohar Wildlife Sanctuary, Mudumalai Wildlife Sanctuary

Ex-situ Conservation 

Ex-situ conservation of biodiversity is the preservation of various species of animals and plants outside their natural environment or habitat. In this type of conservation, breeding of endangered species is done in artificial ecosystems like zoos, botanical gardens, nurseries, etc.


Biodiversity Conservation Strategies

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The strategies that should be followed for biodiversity conservation are:

  • Agricultural animals, livestock, plants like timber plant should be protected
  • The population of endangered species should be restored
  • Natural resources should be utilized efficiently
  • Incessant deforestation should be stopped
  • Hunting should be banned 
  • Spread of public awareness

Importance of Biodiversity Conservation

There is a dire need for the conservation of biodiversity in maintaining a pollution-free environment and ensuring the proper availability of resources to human beings.

  • Humans are completely dependent on nature for various resources like renewable and non-renewable.
  • These resources are provided by animals and plants directly or indirectly. To sustain life on earth the rich flora and fauna of the Earth has to be conserved efficiently.
  • Biodiversity supports the food security and livlihoods throughout the genetic diversity.
  • It has also contributed in advanced medicines and human health treatment.

Things to Remember

  • Biodiversity refers to a variety of living species that interact with one another.
  • The deduction in the number, genetic variation, and species is called biodiversity loss.
  • Increase in levels of carbon dioxide is one of the causes of loss in the diversity.
  • Machine learning is used to count and identify variety of species in a system.

Previous Years Questions

  1. Which is wrong with respect to our responsibility as a human being to protect our environment? [JEE Mains 2019]
  2. BOD stands for? [JEE Mains 2016]
  3. Biochemical Oxygen Demand (BOD) value can be a measure of water pollution caused by the…? [JEE Mains 2016]
  4. Ozone is destroyed by CFCs in the upper stratosphere Ozone holes increase the amount of UV…? [JEE Mains 2019]
  5. Addition of phosphate fertilisers to water bodies causes? [JEE Mains 2015]
  6. A water sample has ppm level concentration of the following metals…? [JEE Mains 2019]
  7. Calcium metabolism in birds gets disturbed due to...[KEAM]
  8. The distribution of species diversity on earth may be best described as...(AMUEEE 2015)
  9. Which one of the following is not included under in-situ conservation ?..(AMUEEE 2012)
  10. An ecologist uses the term biodiversity for the variety of species of...(AMUEEE 2013)
  11. Kanha National Park is located in ............ and is famous for ................(AMUEEE 2012)
  12. Which of the following is not an example of in situ conservation ?(AMUEEE 2013)
  13. What is the main cause for the extinction of some species in tropical forests….​(BHU UET 2006)
  14. Endangered plant species are conserved through...(COMEDK UGET 2015)
  15. _____is a national park in Kamataka..(COMEDK UGET 2009)
  16. Western Ghats have come under "Hot spot" category because of...(COMEDK UGET 2007)
  17. Write the present expansion for WWF...(COMEDK UGET 2008)
  18. Alexander Von Humbolt described for the first time:….(NEET 2017)
  19. All of the following are included in �Ex-situ conservation� except...(NEET 2018)
  20. Which of the following is the largest taxon among plants in terms of the number of species ?​...(AMUEEE 2014)

Sample Questions

Ques.What is meant by biodiversity? (1 Mark)

Ans. All species of flora and fauna existing on Earth come under biodiversity.

Ques.What are the different types of biodiversity? (1 Mark)

Ans. Genetic diversity, Species diversity, ecological diversity.

Ques.What is meant by biodiversity conservation? (1 Mark)

Ans. The conservation of various species of plants and animals for the proper maintenance of life on earth is known as biodiversity conservation.

Ques.What are the different methods of biodiversity conservation? (2 Marks)

Ans. There are two methods of biodiversity conservation namely:

  1. In-situ conservation
  2. Ex-situ conservation

Ques.What are the reasons behind the loss of biodiversity? (1 Mark)

Ans. The main reasons for biodiversity loss are population explosion/overpopulation, extensive mechanization/industrialization, urbanization, deforestation, pollution, soil erosion, depletion, etc.

Ques.What are the measures that should be taken for biodiversity conservation? (2 Marks)

Ans. The various measures that should be taken for the conservation of biodiversity are planting more and more trees, hunting and deforestation should be banned, the population should be controlled, awareness should be created in public for biodiversity conservation. 

CBSE CLASS XII Related Questions

  • 1.
    Student to attempt either option (A) or (B):
    (A)
    (i) Explain why the milk produced by the mother during the initial days of lactation is considered to be very essential for the newborn infant.
    (ii) What is the term used for the milk produced during the initial days of lactation?
    OR
    (B) Many children in the metro cities are suffering from a very common exaggerated response of the immune system to certain weak antigens in air.
    (i) What is the term used for the above mentioned disease?
    (ii) Name the main type of antibody produced by the immune system in response to this disease.
    (iii) Which two main inflammation-causing chemicals are produced by the mast cells in such an immune response?


      • 2.

        Student to attempt either option-(A) or (B):
        (A) Write the features a molecule should have to act as a genetic material. In the light of the above features, evaluate and justify the suitability of the molecule that is preferred as an ideal genetic material. 
        OR 
        (B) Differentiate between the following:

        • [(i)] Polygenic Inheritance and Pleiotropy
        • [(ii)] Dominance, Codominance and Incomplete dominance


          • 3.

            Answer the following questions:

            [(i)] Explain the structure of a mature embryo sac of a typical flowering plant.

            [(ii)] How is triple fusion achieved in these plants?

            OR

            [(i)] Describe the changes in the ovary and the uterus as induced by the changes in the level of pituitary and ovarian hormones during menstrual cycle in a human female.


              • 4.

                Student to attempt either option (A) or (B).
                (A) 
                (i) Describe the process of megasporogenesis in an angiosperm. 
                (ii) Draw a diagram of a mature embryo sac of the angiosperm. Label its any four parts. 
                OR
                (B) The reproductive cycle in the female primates is called menstrual cycle. The first menstruation begins at puberty. 
                Answer the following questions: 
                (i) Name the four phases of menstrual cycle in a proper sequence. 
                (ii) How long does the menstrual phase last in a menstrual cycle? 
                (iii) When and why hormones estrogen and progesterone reach their peak levels respectively, in the menstrual cycle? 
                (iv) Give the significance of LH surge.


                  • 5.
                    Why are restrictions imposed on MTP in India? Up to how many weeks or trimesters, is MTP considered relatively safe for a female, if necessary to perform, by a medical practitioner?


                      • 6.
                        Describe the structure and working of a sparged stirred-tank bioreactor.

                          CBSE CLASS XII Previous Year Papers

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