2nd PUC Biology Question Bank Chapter 15 Biodiversity and Conservation

You can Download Chapter 15 Biodiversity and Conservation Questions and Answers, 2nd PUC Biology Question Bank with Answers, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Biology Question Bank Chapter 15 Biodiversity and Conservation

2nd PUC Biology Biodiversity and Conservation NCERT Text Book Questions and Answers

Question 1.
Name the three important components of biodiversity.
Answer:
Genetic diversity, species diversity, and ecological diversity.

Question 2.
How do ecologists estimate the total number of species present in the world?
Answer:
Ecologists make a significant comparison of species richness of exhaustively studied groups of insects of the temperate and tropical regions and extrapolate this ratio to other groups of animals and plants to calculate a gross estimate of the total number of species existing on the earth.

Question 3.
Give three hypotheses for explaining why tropics show the greatest levels of species richness.
Answer:
a. Tropical regions have remained relatively undisturbed for millions of years and thus had a long time for species diversification.
b. Tropical environments are less seasonal, relatively more constant, and predictable.
c. Availability of more solar energy and contributes much productivity.

Question 4.
What is the significance of the slope of regression in a species-area relationship?
Answer:
When analysis of species-area relationships is done among small areas, the values of the slope of regression are remarkably similar regardless of the taxonomic group or the region. However, when such analysis is done among very large areas, i.e., continents, then the slope of regression would be much steeper. Biodiversity also changes with the change in altitude. It increases from higher to lower altitudes.

Question 5.
What are the major causes of species losses in a geographical region?
Answer:
Causes of biodiversity losses:
The extinction of species and consequent loss of biodiversity is due to mainly four major reasons. The Evil Quartet is the sobriquet used to describe them.

Question 6.
How is biodiversity important for ecosystem functioning?
Answer:
Biodiversity is useful in ecosystem services. Maintenance and sustainable utilisation of useful products and services of various ecosystems as well as individual species require the presence of biodiversity. The rich biodiversity is important for stability, productivity, resilience and ecosystem health. Increased biodiversity contributes to higher productivity. Forest and oceanic systems control climate and maintain gaseous composition of the atmosphere through photosynthesis. Biodiversity is essential for natural pest control, maintenance of populations of various species, pollination by insects and birds, nutrient cycling, conservation and purification of water, formation and protection of soil, etc.

Question 7.
What are sacred groves? What is their role in conservation?
Answer:
Sacred groves are forest patches protected by several tribal communities and religious groups due to the religious sanctity of the forest. Such sacred groves are found in Khasi and Jaintia hills in Meghalaya, Aravalli hills of Rajasthan, Western Ghat regions of Karnataka and Maharashtra. In Meghalaya, the sacred groves are the last refuge for a large number of rare and threatened plants.

Question 8.
Among the ecosystem services are control of floods and soil erosion. How is this achieved by the biotic components of the ecosystem?
Answer:
Biotic components of the ecosystem include plants and animals. Floods and soil erosion are prevented by the producers especially trees present in the ecosystem. The roots of trees bind to the soil firmly thus preventing soil erosion by wind or water. Raindrops in a forest do not hit the floor directly. The canopy layer of the forest intercepts the flow of raindrops so that the rainwater falls on the leaves of trees and then drips slowly onto the forest floor. Thus, water does not collect and stagnate on the forest floor. This prevents flooding. Moreover, trees in the forest also regulate the water cycle.

Question 9.
The species diversity of plants (22%) is much less than that of animals (72%). Give explanation.
Answer:
The great structural and resource heterogeneity provided by plants is the principal reason of high animal diversity. A single plant species can accommodate many animal species.

Question 10.
Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?
Answer:
Certain species are the causal organisms of a number of human diseases which are epidemic. Mostly many disease-causing viruses like Varicella virus, Poliovirus, HIV are harmful to human beings and have no role in ecosystem stability as decomposers. But to eradicate the diseases caused by them, these viruses should be eradicated i.e., made extinct if possible.

2nd PUC Biology Biodiversity and Conservation Additional Questions and Answers

2nd PUC Biology Biodiversity and Conservation One Mark Question

Question 1.
What are endemic species?
Answer:
Those species which are confined to a particular region and are not found anywhere in the world are called endemic species.

Question 2.
Where does the Tiger project is established in Madhya Pradesh?
Answer:
Kanha national park.

Question 3.
Name some biodiversity hotspots in India
Answer:
Western Ghats, Himalayas, Indo-Burma region – Srilanka.

Question 4.
Where do great Indian bustards are found in India?
Answer:
Rajasthan, Punjab, Gujrat.

Question 5.
Some plants are used to extract chemicals used as drugs.
a. Mention the type of products extracted.
b. Give some examples of this product and its uses.
Answer:
a. Botano chemicals.
b. Papaver somniferum – Morphine
Chinchona ledgeriana – Quinine
Taxus brevifolia – Taxol

Question 6.
Which part of the world is known as lesser biodiversity?
Answer:
Poles have lesser biodiversity.

Question 7.
Name the district in Kerala
a. which has the highest forest coverage?
b. which has the lowest forest coverage?
Answer:
a. Idukki
b. Alappuzha (has no forest)

Question 8.
Name the unlabeled areas ‘a’ and ‘b’ of the pie chart representing the global diversity of invertebrates showing their proportionate number of species of major taxa (Delhi 2009)

Answer:
(a) Insects
(b) Molluscs

Question 9.
Name the unlabeled areas ‘a’ and ‘b’ of the pie chart representing the biodiversity of plants showing their proportionate number of species of major taxa. (AI2009)

Answer:
(a) Fungi
(b) Angiosperms.

Question 10.
Name the unlabeled areas ‘a’ and ‘b’ of the pie chart representing the biodiversity of vertebrates showing the proportionate number of species of major taxa. (CBSE 2009)

Answer:
(a) Fishes
(b) Amphibians.

Question 11.
Name 2 animals that have become extinct by overexploitation by humans.
Answer:
Steller’s sea cow and the passenger pigeon.

2nd PUC Biology Biodiversity and Conservation Two Marks Questions

Question 1.
Write the scientific name of the plant that yields reserpine. How is genetic variation expressed in this plant?
Answer:

• Rauwolfia vomitoria are the plant that yields reserpine.
• The genetic variation is shown in terms of the potency and concentration of the active chemical reserpine.

Question 2.
What is social forestry?
Answer:
The planning of social forestry started in India in 1976, which is related to the conservation of forests. This project is useful for local people in various ways, such as fulfills their requirements, provides work to the unemployed, uses wasteland, and help to maintain O₂ and CO₂ balance in the atmosphere, etc. Thus, the project is started by the Indian government, the chief objectives of this project are as follows:

• Plantation of useful plants in the forest.
• Development of forests on personal lands by the cooperation of government.
• To prevent the harmful effects of pollution by the development of artificial forests.
• Preservation of endangered wild animals.

Question 3.
Explain co-extinction.
Answer:
It is a phenomenon in which when a species becomes extinct, the plant and animal species associated with an obligatory manner also become extinct. eg:- When a host fish becomes extinct, its unique assemblage of parasites also faces extinction.

Question 4.
Differentiate between zoological and national parks
Answer:

Zoological park	National park
These are the areas where the threatened animals are kept under conditions very similar to their natural habitat.	These are large areas where animals and plants are protected in their natural habitat.
It is an exsitu method os conser­vation.	It is an in situ conservation method.

Question 5.
What are biosphere reserves? How many of them are present in India?
Answer:
Biosphere reserves are the ecologically unique and bio-diversity-rich regions that are legally protected. There are 14 biosphere reserves in India.

Question 6.
Why does the introduction of alien species into an ecosystem cause loss of biodiversity?
Answer:
The alien species become invasive and resources, so there is a decline in the indigenous species.

Question 7.
Name the region of the earth called the “lungs of the planet”. Mention giving reasons, the activities which are being carried out in this region now.
Answer:
Amazon forest is called the “lungs of the planet”. Human activities which are being carried out in this region are

• Grazing of beef cattle
• Cultivation of soya bean crop.

Question 8.
When and where the convention on biological diversity (earth summit) was held? While its aim.
Answer:

• The earth summit was held in Rio de Janeiro in 1992.
• The aim was to make the nation take appropriate measures for the conservation of biodiversity and sustainable utilization of its benefits.

Question 9.
What are sacred groves? Where are they found in India?
Answer:
Sacred groves are the tracts of forests that are set aside where all the trees and wildlife are venerated and given complete protection.
In India, sacred groves are found in

• Kashi and Jaintia Hills in Meghalaya
• Aravalli hills of Rajasthan
• Western Ghat regions of Karnataka and Maharashtra.
• Sarguja, Chanda, and Bastar areas of M.R
• Sarpakavu of Kerala.

Question 10.
Write any five features of Indian forests.
Answer:
Indian forests are characterized by :

1. Indian forests are mainly tropical forests.
2. Himalayan forests are characterized by the presence of coniferous trees.
3. In few parts of our country having temperate forests.
4. Our forests contain a large number of useful varieties of plants and animals.
5. Great variations are present in Indian forests.

2nd PUC Biology Biodiversity and Conservation Three Marks Questions

Question 1.
Differentiate between In situ conservation and Ex-situ conservation.
Answer:
In situ conservation:- It is the method of protecting the endangered species of plants or animals in the natural habitat either by protecting or cleaning up the habitat itself or by defending the species from predators.

• It helps in recovering populations in the surroundings where they have developed their distinct features.

Ex-situ conservation:-

• It is the method of protecting the endangered species of plants or animals by removing them from the unsafe or threatened habitat and placing them under the care of humans.
• It helps in recovering or preventing their extinction under stimulated conditions.

Question 2.
What are the characteristics of a stable community?
Answer:

• A stable community does not show much variation in productivity from year to year.
• Such a community must be either resistant or resilient to occasional disturbances both natural and man-made.
• It must be resistant to invasions by alien species.

Question 3.
Differentiate between Genetic diversity and species diversity.
Answer:

Genetic diversity	Species diversity
(a)  It is a trait of the organisms. (b)  It represents the variety of genetic information present in the organisms. (c)  It is important for adaptation to the enviro­nment and changes occurring in it.	(a) It is a trait of the biotic community. (b) It is a variety of species and their abundance found within a region. (c) It influences the stability of the ecosystem.

2nd PUC Biology Biodiversity and Conservation Five Marks Question

Question 1.
What is the influence of biodiversity on the ecosystem? Mention the 3 possible consequences that loss of biodiversity in a region can lead to.
Answer:
Influences of biodiversity

• The ecosystems with more species diversity show less year-to-year variation in total biomass production.
• The ecosystem with species diversity shows more productivity compared to those with less species diversity.

Consequences are
The loss of biodiversity can lead to

• A decline in the crop productivity
• Increased variability in a certain ecosystem
• A decreased resistance to environmental perturbates like drought.

Question 2.
Prepare a notice to be distributed to the lower classes on the importance of the ‘Conservation of Biodiversity’.
Answer:
The great biodiversity on earth is vital for the existence of mankind.
The reasons for conserving biodiversity are the following.

i. Narrowly utilitarian: This argument for conserving biodiversity are obvious i.e., humans derive countless economic benefits such as food, firewood, fiber, construction materials, industrial products (such as tannins, dyes, lubricant, resins, perfumes etc.), medicinal products etc. More than 25% of medicines are derived from plants and nearly 25,000 species of plants contribute to the traditional medicines used by the native peoples around the world. It is unknown that how many medicinal plants are waiting to be explored in the tropical rain forest.

ii. Broadly utilitarian: This argument says that biodiversity plays a vital role in all ecosystem services. Amazon rain forest alone produces 20% of the total oxygen in the atmosphere through photosynthesis. Can you estimate the economic value of this life-saving gas provided by nature? The other indirect benefits that we receive are
a. Pollination: Without pollination, the plants cannot give us fruits and seeds. The pollination is done by bees, birds, bats etc.

b. Aesthetic and cultural benefits: The aesthetic values include ecotourism, bird watching, wildlife, pet-keeping, gardening, etc. Plants like Tulsi (Ocimum sanctum), Pipal (Ficus religiosa) etc. are considered sacred and are used by many Indians for religious purposes. Nowadays we recognize plants and animals as symbols of national pride and cultural heritage. Walking through a forest, watching spring flowers in full bloom or waking up to a bulbul’s song in the morning etc. also gives pleasure and smoothness.

iii. Ethical argument: This says that we have a moral responsibility to take care of earth’s biodiversity such as millions of plants, animals, microbes etc. with whom we share this planet. We need to realize philosophically or spiritually that each and every species on the earth has its own intrinsic value.

Question 3.
“Ecology is permanent economy”. This is the Chipko slogan coined by Sundarlal Bahuguna. Write a short note on Chipko Movement.
Answer:
It is one of the People’s movements in biodiversity conservation. The Chipko Movement is the result of hundreds of decentralized and locally autonomous initiatives. Its leaders and activists are primarily village women, acting to save their means of subsistence and their communities. Men are involved too, however, and some of these have given wider leadership to the movement. Prominent Chipko figures include: Sunderlal Bahuguna, a Gandhian activist and philosopher, whose appeal to Mrs. Gandhi resulted in the green-felling ban and whose 5,000-kilometer trans-Himalaya foot march in 1981-83 was crucial in spreading the Chipko message. Bahuguna coined the Chipko slogan: ‘ecology is the permanent economy’.

Question 4.
Describe the National and International efforts prescribed for the conservation of forests.
Answer:
Forest conservation is started in India on a national level by the British government. In 1856, Lord Dalhousie had formulated a policy for the conservation of forest in Burma. In 1894, the Indian government also prepared a forest policy on a national level. The main points of this policy are:

• Forest management,
• Proper use of forest land,
• Policy for protected forests,
• Improved forest production.

The Indian government established national parks, sanctuaries, and zoological parks. The F.A.O. of the United Nations is also functioning on forest conservation on an international level. This organization also provides financial help for this purpose. In 1952, the Indian government also prepared India’s New National Forest Policy under the direction of F.A.O. Forest policy has been planned for

• Prevention of deforestation of hill plants.
• Reforestation of grazing land.
• Development of grazing land,
• Plantation of economically useful forest trees.
• Increase in the profit of government from forests.

Question 5.
Which are the different “methods of in situ conservation?
Answer:
In situ conservation is the process of protecting the whole ecosystem and its biodiversity at all levels. The endangered species of plants and animals are protected in their natural habitat without disturbing them from their own habitat. It helps in recovering the population in the surroundings where they have developed their distinctive features.

• Hotspots -These are the regions with high levels of species richness and a high degree of endemism to provide maximum protection.
• Biosphere reserves – These are ecologically unique and biodiversity-rich regions that are legally protected. In India, there are 14 biosphere reserves.
• National park and wildlife sanctuaries- These are the places where animals are in their own undisturbed habitat but protected these areas by law.
• In India, there are 90 national parks and 448 wildlife sanctuaries are there.
• Sacred groves – These are some patches of forest where all the trees and wildlife within are venerated and given total protection, eg: Sarpakavu in Kerala. Sarguja area of M.P. etc.