Biodiversity and Conservation Class 12 Notes CBSE Biology Chapter 15 (Free PDF Download)

Section−A (1 Mark Questions)

1. What type of biodiversity is represented by the following? 

(i) The Amphibian population is richer in the Western Ghats than the Eastern Ghats.

(ii) Variation in the potency and concentration of the reserpine in Rauwolfia.

Ans. (i) Species diversity

(ii) Genetic diversity

2. How many species of plants and animals have been described by IUCN in 2004? What is global species diversity according to Robert May?

Ans. IUCN (2004) has described slightly more than 1.5 million species of plants and animals. According to Robert May’s estimates, the global species diversity is about 7 million.

3. Explain co-extinction with a suitable example.

Ans. When a species becomes extinct, the plant and animal species associated with it in an obligatory way also become extinct. This is known as co-extinction. Example- In plant-pollinator mutualism, extinction of one leads to the extinction of the other.

4. What is the IUCN red list? 

Ans. IUCN (International Union of conservation of nature and natural resources) maintains a “Red data list” which is a catalog of taxa facing the risk of extinction. 

5. What are endemic species?

Ans. Species exclusively confined to one region and nowhere else in the world are endemic species.

Section−B (2 Mark Questions)

6. What do you mean by species diversity? Name two measures of species diversity.

Ans. Species diversity refers to the variety of species within a particular region. The two important measures of species diversity are:-

(i) Species richness:- It refers to the number of species per unit area.

(ii) Species evenness:- It refers to the relative abundance of different species is represented in an area.

7. What are sacred groves? What is their role in conservation?

Ans. Sacred groves are forests and natural habitats that are protected through religious faith and worship, by the locals of a region. In many cultures, some forest tracts were set aside. The trees and wildlife within those tracts were venerated (considered holy) and given total protection. In some areas, the sacred groves are the last refuges for a large number of rare and threatened plants.

8. Give reasons as to why is it difficult to estimate global diversity for prokaryotes.

Ans. It is difficult to estimate the global diversity of prokaryotes because

(i) Conventional taxonomic methods are not suitable for identifying microbial species.

(ii) Many of these species are not culturable under laboratory conditions.

(iii) If biochemical and molecular biology techniques are used to delineate species, their diversity would run into millions.

9. List the important attributes of a stable community.

Ans. The important attributes of a stable community are:

(i) It must not show too many variations in the year–to–year productivity.

(ii) It must be either resistant or resilient to seasonal disturbances.

(iii) It must be resistant to invasion by alien species.

10. Give below is the graph for the species-area relationship.

Ans. Equation for curve ‘a’: S = CAZ 

Equation for curve ‘b’: Log S = log C + Z log A

where,

S= Species richness

A= Area

Z = Slope of the line (regression coefficient)

C = Y-intercept

11. Name any four approaches each for ex-situ conservation and in situ conservation as a strategy for biodiversity conservation.

Ans. In-situ conservation: Biodiversity hotspots, Sacred groves, Wildlife sanctuaries, Biosphere reserves.

Ex-situ Conservation: Zoological parks, Botanical garden, Arboretum, Gene bank.

PDF Summary - Class 12 Biology Biodiversity and Conservation Notes (Chapter 15)

• Large and diverse communities of biota occupy distinct zone-forming ecosystems.

• The term biodiversity was first coined by W.G. Rosen in the year 1980.

• It is a shortened combination of two words- “biological” and “diversity”.

• Biodiversity or biological diversity is often defined because of the vast diversity of species and sorts of all the life forms existing on earth. They include the species of microorganisms, algae, fungi, plants, animals, occurring on the earth in various habitats and the ecological complexes and niches of which they are apart.

• Whether or not a species can survive and colonize a neighborhood depends on the environmental conditions of the world also because of the range of tolerance of the species.

Magnitude of Biodiversity

• Approximately 45,000 species of plants and nearly twice as many species of animals are found in India. Therefore, India is said to be one of the 12 mega diversity-bearing countries on the planet.

• Numerous species that are yet to be identified are believed to inhabit tropics and coral reefs. 

• The number of species present in the tropics can be estimated by comparing species richness between tropics and temperate areas. Inventories are nearly complete for most groups of organisms in temperate areas. 

• Scientists have calculated approximately 5.50 million species of organisms present in the world. 

• The most interesting aspect of biodiversity is that more than ${ 70 }$% of all species are animals while plants account for only ${ 22 }$%. 

• Among the animals, insects are the most numerous at about ${ 70 }$% with a present estimate of 7 out of 10 animals. 

• The knowledge about protists, archaebacteria, and viruses is somehow less and with the help of that information, the magnitude of biodiversity will increase further.

Levels of Biodiversity 

1. Genetic Diversity 

• It is the diversity in the number and type of genes as well as chromosomes present in different species and also the variations in the genes and their alleles in the same species. 

• On average a bacteriophage has 100 genes, Drosophila melanogaster has 13000 genes, whereas the Homo sapiens has 30,000 – 40,000 genes. 

• Variation in the genes of a species increases with the increase in size and environmental parameters of the habitat. 

• Genetic diversity is useful in adapting to changes in environmental conditions. 

• It helps in the speciation or evolution of new species. 

• Lower genetic diversity within a species or variety is very much useful for uniformity in yield as well as higher yield.  

• At the hands of fungal or insect attacks, the lower genetic diversity is more susceptible to degradation and prone to mass-scale destruction. 

2. Species Diversity 

• It is the diversity and variety in the number and richness of the species of a particular region. 

• Species richness is the number of species present per unit area. 

• Species evenness or species equitability is represented by the number of individuals of different species in a given area. 

• Those communities exhibit evenness where species are represented by more or less the same number of individuals. 

• Communities where one or more species have more individuals than others show dominance or unevenness. 

• The product of species richness or evenness or equitability is known as species diversity.  

• Odum et al in the year 1960 calculated species diversity as several species per thousand individuals whereas Menhinick in the year 1964 calculated it as the number of species about the square root of a total number of individuals.

• The Shannon index is the diversity index commonly used in ecological studies. 

3. Community and Ecosystem Diversity 

• Community Diversity is of Three Types:

(i) Alpha diversity exists within community diversity. It is species diversity that is dependent upon species richness and evenness. Amongst the members of the same community, there is a lot of competition, adjustments, and inter-relationships. Here variations are limited. 

(ii) Beta diversity exists between communities. It appears along a gradient of habitat within the geographical area. Due to differences in microhabitat, niches, and environmental conditions, there may occur changes in communities that could lead to the replacement of species. 

(iii) Gamma diversity is the diversity that is present in ranges of communities as represented by the diversity of habitats or ecosystems over a total landscape of the complete geographical area. 

• Ecosystem diversity is the variety of forms in the ecosystem due to the diversity of niches, trophic levels, and ecological processes like nutrient recycling, food webs, energy flow, the role of dominant species, and various biotic interactions. 

• Diversity helps in attaining more productive and stable ecosystems which can tolerate various environmental stresses such as prolonged drought. 

India as Mega Diversity Region 

• As India has been assigned the status of mega diversity nation it has attained a unique distinction. 

• The country has 10 biogeographical regions. Trans Himalaya, Himalaya, Desert, Semi-arid, Western  Ghats, Deccan peninsula, Gangetic Plain, Coasts, North-East, and Islands belongs to the biogeographical regions of India.

• India has 89 national parks, 492 wildlife sanctuaries, 14 biosphere reserves, 6 wetlands, and 5 world heritage sites. The country also has 27 tiger reserves. 

• The largest biogeographical region is the Deccan peninsula and the Western ghat and northeast are regions richest in biodiversity. 

• ${ 33 }$% of flowering plants, ${ 10 }$% of mammals, ${ 36 }$% reptiles, ${ 60 }$% of amphibians, and ${ 53 }$% of freshwater fish are endemic. The Himalayas and the Western Ghats are the richest regions. Indian Islands and North-Eastern Hills

Patterns of Biodiversity Latitudinal and Altitudinal Gradients 

(i) Latitudinal Gradient 

• There was little biodiversity at the poles. Biodiversity is more in temperate areas but it occurs maximum in tropical rainforests. This is because the tropical rain forests have more favorable conditions for more varieties of organisms and with fewer or no catastrophes. This has allowed for stability in the environment and also allowed more species to develop. 

• Only during the cold season in temperate areas the harsh conditions exist. However, in arctic regions there remains very harsh conditions for most of the year.

• In tropical forests, the number of vascular species is 118-236/0.1 ha, and in temperate forests 21-48 species 0.1 ha. Their number would be 10/0.1 ha in arctic regions.

(ii) Altitudinal Gradient 

• As we ascend high mountains a decrease in species diversity occurs due to a drop in temperature and greater seasonal variability.

Species – Area Relationship 

• Alexander von Humboldt, a German geographer, and naturalist observed that species richness within a region increases with the increasing area but only up to a certain limit. 

• For a wide variety of taxa whether they are birds, bats, freshwater fishes, or flowering plants the relationship between species richness and area is a rectangular hyperbola. 

• It is represented as a straight line on a logarithmic scale. 

• Here species richness is represented by S,  the slope of the line or regression coefficient is represented by Z, C represents the y-intercept whereas A represents the area. 

• The regression coefficient is generally 0.1-0.2, regardless of taxonomic group or region e.g. plants found in Britain, birds that are seen in  California, or mollusks that exist in New York.  

• However, when the species-area relationship is considered for a very large area like the whole continent, the geographical retrogression coefficient or slope of the line will have a Z value of 0.6 – 1.2, e.g. frugivorous birds and mammals of tropical forests of different continents will represent a steeper line of 1.15. 

Importance of Biodiversity 

1. Source of Food 

• Out of 3000 species of food plants, only 150 species have been commercialized. It can be seen that ${ 85 }$% of the food output is produced by less than 20 species. 

• Two-third of food is being produced by only three crops that are rich in carbohydrates: wheat, corn or maize, and rice. 

• Utilization of more and more food plants has to be made.

2. Source of fats and oils 

• The major oilseed plants are soybean, coconut, cottonseed, peanut and sunflower, sesame, safflower, mustard, and oil palm. 

• For obtaining high-performing lubricants some newer species of oil are being investigated. E.g. Bitter colocynth, and jojoba seed.

3. Fibres 

• The major sources of fiber are cotton, jute, flax, hemp, sun hemp, rosella, coir, and agave. Search is continuously going on for new superior fiber yielding plants.

4. New Varieties 

• Domesticated commercial species have been improved for various traits, especially disease resistance by crossing them with their wild relatives. 

• Rice has been made resistant to four main diseases by crossing it with its wild species namely Oryza nivara from India. 

• Potato has been made resistant to late blight (a trait from Solanum demissum), Potato Mosaic Virus Y (a trait from  Solanum stolonifera), Fusarium, and five races of cyst nematodes (a trait from Solanum spegazzini)

5. Drugs and Medicines 

• Several drugs are based on plant products. 

• Rosy periwinkle (Catharanthus roseus = Vinca rosea) yields alkaloids (Vincristine and vinblastine) which are useful for the treatment of leukemia. The same is now being synthesized chemically. 

• Other drugs derived from plants are Morphine (Papaver somniferum for pains), quinine (from the bark of Cinchona ledgeriana for malaria), taxol (from the bark of Yew; Taxus brevifolia and Taxus baccata for treating cancers),  reserpine (from Rauwolfia serpentina for treating blood pressure and schizophrenia), etc. 

• ${ 25 }$% of all drugs are currently sourced from 120 species of plants. 

• Traditional systems of medicine the world over use thousands of local or wild plants for treating various maladies. Plant chemicals are also called botany chemicals and it is possible to manufacture innumerable synthetic products from Plant chemicals.

6. Aesthetic Value 

• Biodiversity features a lot of value in terms of aesthetics and attraction of individuals towards a specific place. Biodiversity's aesthetic value is frequently exploited in ecotourism, bird watching, wildlife conservation, pet ownership, and gardening.

7. Cultural Benefits 

• Historically people have attached themselves to certain specific plants and animals. 

• Many Indian homes have varieties of Ocimum sanctum (Tulsi) growing in the gardens and pots. 

• Trees of Ficus religiosa commonly called Peepal and Prosopis cineraria known as Khejri are considered sacred. They are worshipped too.

• Many birds are believed to be sacred. Snakes are also worshipped. 

• Every country and state recognizes a particular plant and particular animal as a symbol of national and state pride and cultural heritage. 

8. Ecosystem Services 

• Biodiversity is required to maintain and utilize products and services of various ecosystems and individual species. 

• Forest and oceanic systems control climate and maintain the gaseous composition of the atmosphere. 

• Amazon rain forests are considered the lungs of planet earth as they give out  ${ 28 }$% of total oxygen. 

• Biodiversity is essential for natural pest control and the maintenance of populations of various species. It is very important for pollination by insects and birds, nutrient cycling, conservation and purification of water, formation, and protection of soil, etc. The services are valued at 16-54 trillion dollars per annum.

Threats to Biodiversity 

The world is facing an accelerated rate of species extinction, largely due to human interference. There are four major  causes which are also called the evil quartet: 

i) Habitat Loss and Fragmentation: - 

• Overpopulation, urbanization, and industrialization require additional land every year. 

• It can come through the destruction or fragmentation of natural habitat through filling wetlands, plowing grasslands, cutting down trees, burning a forest, and clearing some area of vegetation. 

• Animals requiring large territories are badly affected. 

• Migrating animals would surely go astray and must get killed.

ii) Overexploitation:- 

• Excessive exploitation of a species, whether a plant or animal reduces the size of its population so that it becomes vulnerable to extinction. 

• In the last 500 years three subspecies of Tiger, dodo, stellar sea cow, and passenger pigeon have become extinct due to overexploitation by humans. 

• Nowadays several marine fish populations are declining around the world.

iii) Alien Species Invasions:- 

• Non-native or alien species are often used inadvertently for their economic and other uses. Many times they become invasive and inhibit the growth and survival of local species. 

• Island ecosystems are the most vulnerable. This is mainly because of their small size and a small number of species. 

• Water hyacinth (Eichhornia crassipes) was introduced with the intent to reduce pollution in Indian waters. 

• It has led to the clogging of water bodies including wetlands in many places. This has resulted in the death of several aquatic plants and animals. 

• Nile perch may be a predator fish that was introduced in Lake Victoria of South Africa. it's since then killed and eliminated the ecologically unique diversity of over 200 native species of small cichlid

iv) Co-Extinctions:- 

• Certain obligatory mutualistic relationships exist in nature e.g. Yucca moth and Yucca flower. 

• The extinction of one will automatically cause the extinction of the other. 

• If the host fish becomes extinct, all the parasites exclusively found on that will automatically become extinct.

Wildlife Conservation 

Wildlife conservation is necessary for a lot of reasons. 

i) Balance of Nature: 

• In an ecosystem, there is a natural balance. The different types of living organisms live together in equilibrium. 

• The food web consists of an interlocking system of the food chain, the destruction of any species of wildlife in an ecosystem can disrupt the entire balance of nature.

ii) Commercial value of Wildlife: 

• We have a rich variety of wildlife. National parks and sanctuaries which were established by the Government will attract many tourists from abroad. This is a valuable source of foreign exchange. 

• Surplus animals are sold to international zoos and parks, earning foreign exchange in the process.

iii) Biological studies: 

• Naturalists, zoologists, and behavior biologists can study the ecology, physiology, and behavior of the varied sorts of wildlife in their natural habitats. This improves our knowledge of biology.

iv) Sports and Recreation: 

• The sport of hunting is restricted to an excellent extent due to the rapidly declining number of animals. Good recreation is often provided within the sort of camping, trekking, and other adventure activities by wildlife centers.

Conservation of Biodiversity 

Conservation of biodiversity is considered under three categories 

A. Narrowly utilitarian 

B. Broadly utilitarian 

C. Ethical

Narrowly Utilitarian 

• Human beings obtain several direct economic benefits from nature. 

• Food like cereals, pulses, fruits, etc., then firewood, fiber, construction material are obtained from nature.  

• Industrial products such as tannins, lubricants, dyes, resins, perfumes are also made using natural products. 

• Products of medicinal importance too. 

• Bioprospecting is the method of exploring genetics and species-level diversity to get and develop products of economic importance.

Broadly Utilitarian 

• Amazonian forests alone produce nearly ${ 20 }$% of oxygen during photosynthesis. 

• Pollinator layer: bees, bumblebees, birds, and bats that pollinate the plant without which seed cannot be produced by plants.  

• The aesthetic pleasure we get from the conservation of biodiversity.

Ethical:  

• Humans depend on their existence to all other organisms that inhabit and have inhabited this earth.  

• Each species and variety has its intrinsic value.  

• It is our moral obligation to safeguard and pass on the biological legacy that we have been given.

Conservation of Biodiversity: 

There are two types of conservation strategies – in situ (on-site) and ex-situ (off-site) 

1. In situ Conservation 

• It is the conservation and protection of the whole ecosystem and its biodiversity at all levels to protect the threatened species. It is however neither economically possible nor possible to conserve all existing biological wealth and all the existing ecosystems. 

2. Hot spots 

• These are areas with a high density of biodiversity or megadiversity. These are also the most threatened ones. Ecological hot spots are determined by the following four factors: 

(i) Number of species or species diversity 

(ii) Degree of endemism 

(iii) Degree of threat to a particular habitat due to its degradation and fragmentation 

(iv) Degree of exploitation: 

• Mayers (1988) initially identified 12 hot spots with ${ 14 }$% of plant species in an area of only ${ 0.2 }$%. 

• Today the number of hotspots identified by ecologists is 34 covering an area of less than ${ 2 }$% of land surface with about ${ 20 }$% of the human population living there. 

• India has three hot spots: Indo-Burma, Himalayas and the Western Ghats, and Srilanka. 

Protected Areas 

• They are ecological or biogeographical areas where biological diversity is protected, maintained, and managed through legal or other effective measures along with natural and cultural resources. 

• They are defined and delimited based on biological diversity e.g. cold desert in Thar, a wetland in Assam, saline swampy area of Sundarbans, etc. Protected areas involve national parks, sanctuaries, and biosphere reserves.

National Park 

• They are government-managed areas set aside for the enhancement of wildlife cultivation. In National parks, human activities such as grazing, forestry, and habitat manipulation are not allowed. 

• 89 national parks in India occupy nearly ${ 1.1 }$% of the geographical area

Sanctuaries 

• They are large swaths of land with or without lakes where wild animals and flora can hide from hunters. Certain other humans interfering activities such as the collection of forest products, harvesting of timber, private ownership of land, tilling of land, etc., are allowed.

Biosphere Reserves 

• They have protected areas that have been designed for multiple purposes. They are created to preserve genetic diversity in representative ecosystems of various natural biomass and unique biological communities.  This is done by protecting wild populations, traditional lifestyles of tribal and domesticated plant and animal genetic resources. 

• The creation of biosphere reserve was initiated in 1975 under the MAB program of UNESCO. 

• Till the year 2002, there were 408 biosphere reserves had been established in 94 countries. 

• In India, 17 biosphere reserves have been set up by now. 

• Each biosphere reserve has:

i) Core or Natural zone: No human activity is allowed. The area is an undisturbed and legally protected ecosystem. 

ii) Buffer zone: It surrounds the core area. Human activities such as resource consumption, strategy development, and education is restricted.

iii) Transition zone: It is the outermost or peripheral part of the biosphere reserve where active cooperation is present between reserve management and local people for activities like settlements, cropping recreation, forestry, and other economic uses without making any disturbance to ecology.

The transition zone has different parts like forestry, agriculture, and tourism, and restoration regions. 

• Restoration region is a degraded area that is selected for restoration to near natural form.

a. Importance of Biosphere Reserves Includes: 

i) Restoration – Biosphere reserves help in the restoration of degraded ecosystems and habitats. 

ii) Conservation – They aid in the conservation of genetic resources, animals, ecosystems, and landscapes while avoiding uprooting local populations.

iii) Development –By maintaining cultural, social, and ecological sanctity they ensure sustainable economic development. 

iv) Monitoring- Regular monitoring of development and conservation progress is necessary to be done. 

v) Education and Research –Each biosphere reserve promotes teaching and study in the ecosystem/different biome's ecological features. There is also an exchange of information about research, restoration, conservation, and development aspects at the national and global levels.

b. MAB Program 

• Man and biosphere program is an international biological program of UNESCO which was started in 1971 but was introduced in India in 1986. 

• MAB has studied the impact of human interference and pollution on abiotic and biotic components and develops conservation strategies for the present as well as the future. 

c. Ex-Situ Conservation 

• These are means of conservation of any desired species or variety far away from their natural habitats. They are off-site collections.

• They are live collections of untamed and domesticated species in botanical gardens, zoos, etc.

• Currently, there are quite 1500 botanical gardens and arboreta (gardens with trees and shrubs) with quite 8000 species.

• Many of them possess seed banks, tissue culture facilities, and other ex-situ technologies.

• There are more than 800 zoological parks.

• Together they need about 3000 species of mammals, birds, reptiles, and amphibians.

• Most of them also have a well-managed captive breeding program.

• Captive breeding is resorted to in those cases where the amount of surviving individuals is so small that there's no realistic chance of in-place survival.

• As the number of surviving organisms increases, individuals are selectively released within the wild.

• Offsite collection could also be used to replenish depleted populations, reintroduce wild species, and repair degraded habitats.

d. Gene Bank 

• Seed banks, live growing plants (Orchards), tissue cultures, and frozen germplasm with the full range of genetic variety are all maintained by these institutes.

(i) Seed banks: Seeds are of two types- orthodox and recalcitrant.

• Orthodox seeds are those which can tolerate a reduction in moisture content up to ${ 5 }$%, anaerobic conditions, and low temperature of to or even lower for prolonged periods e.g. cereals, legumes.

• Seeds are allowed to germinate at intervals into plants and thus fresh seeds are developed for storage.

• Recalcitrant seeds are those seeds that get killed on reduction of moisture and exposure to lower temperature e.g. Tea, cocoa, jackfruit, coconut.

• They can be stored for a shorter duration after treatment with fungicides in rooms having air and normal oxygen.

(ii) Orchards: Orchards are grown from plants with recalcitrant seeds. At orchards, all possible strains and varieties are maintained e.g. Litchi, oil palm, rubber tree, etc.

(iii) Tissue culture: it's administered through callus formation, embryoids, pollen grain culture and shoot tip culture for those plants which are either seedless, have recalcitrant seed, variable seed progeny, or where a clone is to be maintained.

• The method is beneficial in maintaining an outsized number of genotypes during a small area, rapid multiplication of species, and for hybrid rescue.

• Shoot tip cultures are often wont to maintain virus-free plants. It is used for the international exchange of germplasm in cultures multiplied by vegetative methods. e.g. Banana, Potato.

(iv) Cryopreservation: Preservation at 196°C (liquid nitrogen) can maintain tissue culture, embryos, animal cells/tissue, and spermatozoa indefinitely.

Special processes are used to bring the cryopreserved material back to life when it is needed.

Biodiversity act (2002) 

• To safeguard India's rich biodiversity and associated knowledge against misuse by foreign persons and organisations who do not share the advantages that result from such use, as well as to combat biopiracy.

Convention on Biodiversity

• “The Earth Summit” held in Rio de Janeiro within the year 1992 called upon all nations to require suitable required measures for the conservation of biodiversity and sustainable utilization of its benefits.

• In the World Summit on Sustainable development held in the year 2002 in Johannesburg, South Africa, 190 countries pledged their genuine commitment to achieving by the year 2010 a big reduction within the current rate of biodiversity loss at the worldwide, regional, and native level.

• To safeguard India's rich biodiversity and associated knowledge against misuse by foreign persons and organisations who do not share the advantages that result from such use, as well as to combat biopiracy.

Convention on Biodiversity 

• “The Earth Summit” held in Rio de Janeiro in the year 1992 called upon all nations to take suitable required measures for the conservation of biodiversity and sustainable utilization of its benefits. 

• In the World Summit on Sustainable development held in the year 2002 in Johannesburg, South Africa, 190 countries pledged their genuine commitment to achieving by the year 2010 a significant reduction in the current rate of biodiversity loss at the global, regional, and local level. 

CBSE Class 12 Biology Revision Notes Chapter 15 - Biodiversity and Conservation

Class 12 Biology Chapter 15 Revision Notes Preparation

Class 12 Biology Chapter 15 revision notes online are prepared with the help of expert professionals who are updated with the latest edition of NCERT. Available in the form of PDF files, these can easily be downloaded from the online platform for free. Besides, students can fetch other related documents online through established educational platforms like Vedantu. Mock test papers, PQYP, sample papers, etc. are available through the internet. Students can practice all of the papers for giving their best shot during examinations. Having know-how about the paper structure, pattern, type of questions, and important topics is a great help for preparations.

Topics Covered in NCERT Class 12 Revision Notes Biology Chapter 15 Solution

Working on the following Class 12 notes Biodiversity and Conservation with the help of the revision plan will work wonders:

• Introduction to Biodiversity and Conservation

• Magnitude of biodiversity

• Invertebrates, vertebrates and plants representing global biodiversity

• Levels of biodiversity including genetic diversity, species diversity, community and ecosystem diversity, alpha diversity, beta diversity, gamma diversity

• India as a mega diversity region

• Patterns of biodiversity latitudinal and altitudinal gradients

• Species-area relationship

• Importance of biodiversity as a source of food, source of fats and oils, fibres, new varieties, drugs and medicines, aesthetic value, cultural benefits and ecosystem services

• Threats to biodiversity that includes habitat loss and fragmentation, overexploitation, alien species invasions and co-extinctions

• Wildlife conservation and its importance

• Balance of nature, the commercial value of wildlife, biological studies and sports and recreation

• Conservation of biodiversity

• About narrowly utilitarian, broadly utilitarian and ethical practices

• Conservation of biodiversity

• In Situ conservation

• Hot spots and factors determining that include number of species, degree of endemism, degree of threat to habitat and degree of exploitation

• Protected areas

• National Park

• Sanctuaries

• Biosphere reserves

• Transition zone

• Importance of biosphere reserves that include restoration, conservation, development, monitoring and education and research

• MAB program

• Ex-situ conservation

• Gene bank that includes seed banks, orchards, tissue culture and cryopreservation

• Biodiversity Act (2002)

• Convention on Biodiversity

In addition to these briefly well-explained topics, students will also get access to multiple Youtube links for more understanding. All the topics mentioned in the above points are part of chapter 15- Biodiversity and Conservation and these are well explained briefly and with the help of charts, paragraphs, pointers, graphs, figures, and other highlights. It is easy to understand the approach for students who can give a quick look before their examination day and get all the information accessed on time.

Why Vedantu For Students?

• Vedantu is a trusted online educational platform.

• The platform comprises a talent pool of teachers and professionals.

• Highly qualified teachers and millions of students are connected on a common platform.

• Passionate teaching and learning are the key attributes of Vedantu.

• Vedantu professionals use easily understood language and techniques to explain concepts related to the subject.

• Students can consult live with teachers and get help with their pending questions.

• Vedantu professors believe that understanding the basics and high-level concepts practically is equally important as gaining high marks.

• Vedantu offers solutions for NEET, IIT, and school-level education.

• NCERT Class 12 revision notes Biology Chapter 15 solution is provided on Vedantu's website as a free PDF download.

• The revision notes help school-level students to a different level by providing a well-framed readymade solution for quick reference.

• Getting connected with Vedantu helps students to solve most of their problems with one simple click.

• Vedantu is an excellent choice for students and their educational needs.

Benefits of Class 12 Biology Revision Notes

• The notes provided by Vedantu help to revise important facts, and topics that you have learned long ago.

• It gains your confidence and reduces anxiety.

• It is a great resource for understanding important and complex topics easily and effectively before the exams.

• The notes help students to understand the big and complex topics in a short time.

• Enable students to strengthen their important concepts.

Other Related Links

Class 12 students are suggested to access the following chapter wise Class 12 Biology revision notes to ace the Biology subject.

• Class 12 Biology Chapter 1 Revision Notes 

• Class 12 Biology Chapter 2 Revision Notes

• Class 12 Biology Chapter 3 Revision Notes 

• Class 12 Biology Chapter 4 Revision Notes 

• Class 12 Biology Chapter 5 Revision Notes 

• Class 12 Biology Chapter 6 Revision Notes 

• Class 12 Biology Chapter 7 Revision Notes 

• Class 12 Biology Chapter 8 Revision Notes 

• Class 12 Biology Chapter 9 Revision Notes 

• Class 12 Biology Chapter 10 Revision Notes  

• CBSE Class 12 Biology Chapter 11 Revision Notes 

• CBSE Class 12 Biology Chapter 12 Revision Notes 

• CBSE Class 12 Biology Chapter 13 Revision Notes

• CBSE Class 12 Biology Chapter 14 Revision Notes