Best Books

Sunday, August 19, 2018

Best Books for NEET 2019

What are the best books to refer for CBSE NEET Entrance Exam?

 “So much to study, so little time” must be the feeling of every NEET UG aspirant right now. If one is aiming to crack NEET 2019, choosing the best books for NEET 2019 is undoubtedly the most essential part of the preparation journey. 
Here's Your Answer

Best Books for BIOLOGY

Biology section includes 90 questions which carry 360 marks and it goes without saying that candidates should pay more attention to this section as it carries more weightage. In the list of NEET best books for Biology, we have included books which will help in retaining the concepts and will also prepare them for objective questions. 
1. NCERT TEXTBOOKS Class XI and Class XII

2. Objective NCERT at your Fingertips - Biology
This book is designed as per the fact that most of the questions asked in PMTs are from Biology NCERT books (11th and 12th). It gives chapter-wise, student-friendly synopses for quick-and-easy revision.Objective NCERT

3.Handbook of Biology Paperback by Arihant Experts
The book ‘Handbook of Biology’ is useful for the students of class 11th and 12th who are pursuing the field of Biology. The book covers vast portions of the concepts in Biology. The concepts and descriptions that have been provided in this book follow an easy to understand pattern.Handbook of Biology.

4. NEET/AIIMS Toppers Handwritten Notes-Biology Paperback by Toppersnotes
Toppers handwritten notes are a comprehensive package for the preparation of NEET, AIIMS and other medical entrance examinations, which are designed by Top rankers in NEET & AIIMS. These notes cover all the important topics which are required to crack the exam of NEET. You will find important marked information, short tricks to remember and concise theory to help you memorize easily. These notes are too the point and well researched.Handwritten Notes
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Tuesday, June 19, 2018

Ecology Notes (NEET-2)

 Some cool facts about Ecology
• 75% of all animals are beetles.
• Cockroaches can live weeks without their head (and their heads can
stay alive without their bodies!).
• 70% of the world’s fresh water is stored in Antarctica’s ice.
• Homeowners use up to 10 times more toxic chemicals per acre than
farmers
• In Peru a single bush may contain more ant species than in the British
Isles.
• A single porcupine is known to kill 100 trees in one winter
• Projections for the 21st century indicate that the earth's average
temperature will rise by anything between 1.4 and 5.8

Ecological pyramids:
(1) The number, biomass and energy of organisms gradually decrease from the producer level to the consumer level. This can be represented in the form of a pyramid called ecological pyramid.

(2) Ecological pyramid is the graphic representation of the number, biomass, and energy of the successive trophic levels of an ecosystem.

(3) The use of ecological pyramid was first described by Charles Elton in 1927.

(4) In the ecological pyramid, the producer forms the base and the final consumer occupies the apex.

(5) There are three types of ecological pyramids, namely:

(i) The pyramid of number:
The number of individuals at the trophic level decreases from the producer level to the consumer level. That is, in an ecosystem the number of producers is far high. The number of herbivores is lesser than the producers. Similarly, the number of carnivores is lesser than the herbivores.

(i) In a cropland ecosystem: In croplands the crops are more in numbers. The grasshoppers feeding on crop plants are lesser in number. The frogs feeding on grasshopper are still lesser in number. The snakes feeding on frogs are fewer in number.

                                    Crop -> Grasshopper -> Frogs -> Snakes -> Hawks

(ii) In a grassland ecosystem: In grassland the grasses are there in large numbers. The consumers decrease in the following order.

                                                Grass -> Grasshopper -> Lizard -> Hawk

                                                            Grass -> Rabbit -> Fox -> Lion

(iii) In a pond ecosystem: The number in a pond ecosystem decreases in the following order.

                                    Phytoplankton -> Zooplankton -> Fishes -> Snakes

(b) The pyramid of biomass:
Biomass refers to the total weight of living matter per unit area. In an ecosystem the biomass decreases from the producer level to the consumer level.

(c) Pyramid of energy:
The energy flows in an ecosystem from the producer level to the consumer level. At each trophic level 80 to 90% of energy is lost. Hence the amount of energy decreases from the producer level to the consumer level. This can be represented in a pyramid of energy level to the consumer level. This can be represented in a pyramid of energy
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Monday, June 18, 2018

इन रोचक तथ्यों की जानकारी क्या आपको पता है ?

1. आजतक इतिहास में एक भी ऐसी घटना नही हुई है कि किसी स्वस्थ भेड़िये ने इंसान पर हमला कर दिया हो।

2. धरती पर कीड़ों की उत्पती मनुष्य से पहली हुई मानी जाती है। पहले तो सभी कीड़े एक जैसे थे मगर भिन्न हालातों में रहने के कारण इन की शारीरीक संरचना में थोड़ा-थोड़ा अंन्तर आ गया और इन की कई प्रजातीयां अस्तितव में आ गई।
Types of insects - FactGyan
Insects Classification


3. मधुमक्खियाँ सिर्फ आधा किलो शहद बनाने के लिए बीस लाख फूलों का उपयोग करती है और 1 लाख किलोमीटर से भी ज्यादा यात्रा करती हैं। इतनी यात्रा धरती के ढाई चक्कर लगाने के बराबर है।


4. ग्रामीण इलाकों के एक वर्ग मील के क्षेत्र में जितने कीड़े पाए जाते हैं उनकी गिणती धरती पर मौजुद सभी मनुष्यों से ज्यादा है।
Photo of village FactGyan

5. एक बंबर मक्खी 1 सैकेड में 160 बार अपना पंख हिला सकती है।

6. 85% लोग सोने से पहले वो सब सोचते हैं जो वो अपनी जिंदगी में करना चाहते।
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Ecology Notes (NEET)

Definitions


Population - A group of organisms from the same species who are living together at the same time in the same place that if reproducing sexually can interbreed.

Community - All the populations of different species living together in one area at the same time.

Habitat - The place where a organism species, population or community is living.

Ecosystem - All the communities as well as non-living parts of an area together make up an ecosystem.

Biosphere - All of earth’s ecosystems together make one large ecosystem known as the biosphere.

Producers - Plants and some photosynthetic bacteria who transfer energy from the sunlight into organic compounds which in most cases take the form of carbohydrates.

Consumers - All organisms who consume the energy created by the producers either directly or indirectly.

Productivity - The amount of energy in each organism in each trophic level over a set period of time.


Energy flow:


(1) The transfer of energy from one trophic level to another trophic level is called energy flow.

(2) The flow of energy in an ecosystem is unidirectional. That is, it flows from the producer level to the consumer level and never in the reverse direction. Hence energy can be used only once in the ecosystem.

(3) But the minerals circulate and recirculate many times in the ecosystem.

(4) A large amount of energy is lost at each trophic level.

(5) It is estimated that 90% of the energy is lost when it is transferred from one trophic level to another.

(6) Only about 10% of the biomass is transferred from one trophic level to the next one is a food chain. And only about 10% of chemical energy is retained at each trophic level. This is called 10% law of Lindeman (1942).


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Saturday, June 16, 2018

कुछ रोचक 07 Animal Facts जो आपको किताबों में नही मिलेगें

कुछ रोचक 07 Animal Facts जो आपको किताबों में नही मिलेगें
 
1. बाघ का वैज्ञानिक नाम पेंथेरा टिग्रिस है। यह भारत का राष्ट्रीय पशु भी है। बाघ शब्द संस्कृत के व्याघ्र का तदभव रूप है।



2. भारत के बाघ को एक अलग प्रजाति माना जाता है, जिसका वैज्ञानिक नाम है पेंथेरा टाइग्रिस टाइग्रिस।


3. बाघ की नौ प्रजातियों में से तीन अब विलुप्त हो चुकी हैं।

4. एक आंकड़े के अनुसार 1800 से लेकर 2009 तक बाघों ने 3,73,000 मनुष्यों की जान ली है |

5. विश्व का सबसे छोटा साँप थ्रेड स्नेक होता है। जो कैरेबियन सागर के सेट लुसिया माटिनिक तथा वारवडोस आदि द्वीपों में पाया जाता है वह केवल 10-12 सेंटीमीटर लंबा होता है।


6. कुछ प्रागैतिहासिक प्रजातियां आकार में व्यस्क मानव जितनी उंची तथा वजनी थीं (अधिक जानकारी के लिए नीचे देखें). ये प्रजाति अंटार्कटिक क्षेत्रों तक ही सीमित नहीं थी; बल्कि इसके विपरीत, अंटार्कटिक उपमहाद्वीप के क्षेत्रों में ज्यादा विविधता मिलती थी और कम से कम एक विशाल पेंगुइन उस क्षेत्र में मिला है जो भूमध्य रेखा के 35 से 2000 किमी दक्षिण से ज्यादा दूर नहीं था तथा जहां का वातावरण आज के अपेक्षाकृत ज्यादा गरम था।

7. पेंगुइन को इंसानों से कोई विशेष डर नहीं लगता है और वे बिना हिचकिचाहट के खोजकर्ताओं के समूहों के पास आते हैं। ऐसा शायद इसलिए है क्योंकि जमीन पर पेंगुइन का अंटार्कटिक या पास के अपतटीय टापुओं पर कोई शिकारी नहीं है।
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Friday, June 15, 2018

कुछ रोचक 08 Animal Facts जो आपको किताबों में नही मिलेगें

कुछ रोचक 08 Animal Facts जो आपको किताबों में नही मिलेगें

1. बंदरों को दो वर्गो में बांटा गया है – पहले प्राचीन दुनिया के बंदर जो ऐशिया और अफ्रीका में पाए जाते है और दूसरे नवीन दुनिया के बंदर जो दक्षिणी अमेरिका में पाए जाते हैं।

2. मनुष्यों के सिवाए केवल बंदर ही एकलौते ऐसे प्राणी है जो केलों के छिलके उतार कर खाते हैं।

3. 'छिपकली', रैपटाइल परिवार का सबसे बड़ा प्रजाति समूह है। छिपकली के आलावा रैपटाइल परिवार में सांप, घड़ियाल, मगरमच्छ, मेढक, और कछुआ जैसी अन्य प्रजातियाँ भी शामिल हैं।

4. छिपकली का वैज्ञानिक नाम 'लाकेर्टिलिआ' (Lacertilia) है।


5. हैरानी की बात है कि छिपकली की पूंछ कई बार उसकी सुरक्षा करती है जब भी कोई दुश्मन छिपकली को उसकी पूंछ से पकड़ता है तो छिपकली अपनी पूंछ का वह हिस्सा अपने शरीर से अलग कर देती है।

6. कोमोडो ड्रागन प्रजाति की छिपकली दुनिया की सबसे बड़ी और खतरनाक छिपकली है। यह 10 फुट लम्बी और 300 पौंड भारी होती है। ऐसा कहा जाता है कि कोमोडो ड्रागन इंसानों को भी नहीं छोड़ती है

7. दुनियाभर में छिपकलियों की 5,600 प्रजातियां हैं वैज्ञानिकों के अनुसार छिपकलियों का अस्तित्व धरती पर 200 मिलियन साल पुराना है

8. ‘कुत्ते से सावधान’ यह चेतावनी प्राचीन रोम के एक शहर के घर के दरवाजे पर लिखी पायी गयी हैं. (करीब 2761 साल पहले).

9. FIDO नाम के, अब्राहिम लिंकन के कुत्ते का भी कत्ल किया गया था.


10. ग्रीक और बुलगारिया में एक युद्ध सिर्फ इसलिए लड़ा गया था क्योंकि ग्रीक का एक कुत्ता बुलगारिया का border पार कर गया था.
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Wednesday, June 13, 2018

List of All revolution in India

List of All Revolutions:
• Black Revolution – Petroleum Production

• Blue Revolution – Fish Production

    Dr Hiralal Chaudhary is also considered as the Father of Blue revolution in India.

• Brown Revolution – Leather/non-conventional(India)/Cocoa production

• Golden Fibre Revolution – Jute Production

• Golden Revolution – Fruits/Overall Horticulture development/Honey Production

                 Father Of Golden Revolution : Nirpakh Tutej

• Green Revolution – Food grains

   MSSwaminathan is known as the "Father of Indian Green Revolution" for his leadership       and success in introducing and further developing high-yielding varieties of wheat in India.

   Norman Ernest Borlaug is known as the father of the green revolution.

• Grey Revolution – Fertilizer

• Pink Revolution – Onion production/Pharmaceutical (India) /Prawn production

            Father Of Pink Revolution : Durgesh Patel

• Red Revolution – Meat & Tomato Production -VISHAL TEWARI

• Round Revolution – Potato

• Silver Fiber Revolution – Cotton

White Revolution (In India: Operation Flood) – Milk/Dairy production

         Father Of White Revolution : Verghese Kurien

• Yellow Revolution – Oil Seeds production

• Evergreen Revolution – Overall development of Agriculture
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Tuesday, June 12, 2018

The Living World Notes

Lifethe condition that distinguishes animals and plants from inorganic matter, including the capacity for growth, reproduction, functional activity, and continual change preceding death.

The Living World 

           

Life is the condition that distinguishes animals and plants from inorganic matter, including the capacity for growth, reproduction, functional activity, and continual change preceding death.


Life is a characteristics quality that differentiates an inanimate(non_livings)objects from the animate(living) forms.

CHARACTERISTICS EXHIBITED BY LIVING ORGANISMS –

Growth,
Reproduction,
Ability to sense environment and mount a suitable response,
Metabolism,
Ability to self-replicate,
Self-organise,
Interact and
Emergence.
1. Reproduction process of producing young ones by living things.
                     Asexual Reproduction  do  not  invovle the fusion of gametes or sex cells , e.g, Amoeba
                     Sexual Reproduction  Invovles the fusion of gametes, e.g.,humans

2. Consciousness​   the state of being aware of and responsive to one's surroundings & ability of an organism to sense their environment.

3. Adaptation   Adaptation, in biology, process by which an animal or plant species becomes fitted to its environment.
                            Short Term Adaptation   Temporary changes to responds to changing environment.                                                                       e.g, hibernation and aestivation
                            Long Term adaptation permanent changes in response to changing environment,                                                                          e.g., humming birds

4. Metabolism the chemical processes that occur within a living organism in order to maintain life.

                                 Catabolism involves all of the metabolic processes that tear down biomolecules,
                                 Anabolism is all of the metabolic processes that build biomolecules

5. Thermoregulation Process of regulation body temperature.
                                                       Heat stroke  Increase in body temperature above normal level
                                                       Hypothermia  decrease in body temperature below normal level

​BIODIVERSITY   

Biodiversity the variety of plant and animal life in the world or in a particular habitat, a high level of which is usually considered to be important and desirable. Biological diversity encompasses microorganism, plants, animals and ecosystems such as coral reefs, forests, rainforests, deserts etc

SYSTEMATICS

In biology, systematics is the study and classification of living things; in other words, grouping organisms based on a set of rules (or system).

Two Kinds of Systematics :-Systematics can be divided into two closely related and overlapping levels of classification:

taxonomic (known as the Linnaean System) and phylogenetic.

Taxonomic classifications group living things together based on shared traits - usually what they look like or what their bodies do. For example, animals that lay eggs and have scales we call reptiles, and animals that have live births and have fur or hair we call mammals.
Phylogenetic classifications use the taxonomic names, but further group organisms by how evolutionary related they are to one another.
It is study of the units of the biodiversity, It attempts to classify the diversity of organisms on the basis of following four fields viz,
identification. classification, nomenclature and taxonomy.

Identification It aims to  identify the correct name and position of an organism in the already established classification system It is done with the help of Keys. Key is a list of alternate characters. An organism can be identified easily  by selecting and eliminating the characters present in the key.

Classification  It involves the scientific grouping of identified organism into convenient categories or taxa based  on some easily observable and fundamental characters.

The various categories are kingdom, phylum,class, order, family, genus and species.

Nomenclature After classification, organism are subjected to a format of two-word naming system called binomial nomenclature. It consists of two components, i.e., generic name and specific epithet 
  • For example,  iMangifera indica, 'Mangifera' is the generic name and 'indica'  is the specific name of mango. This system was proposed by C Linnaeus (a Swedish Botanist) in (1753) in his book Species Plantarum.
  • An organism is known by different names in different languages. It would be impossible for any person to remember the names of an organism in all the languages. Hence, there is need for a uniform system of nomenclature of organisms. A uniform system of nomenclature and identification helps the scientists in systematic study of living beings. ICBN (International Code for Botanical Nomenclature) applies to the plants and ICZN (International Code for Zoological Nomenclature) applies to the animals.

  • General Rules for Nomenclature:

  • Biological names are usually written in Latin. They are written in italics.
  • A biological name usually contains two terms. The first term shows the genus, while the second term shows the species.
  • Biological name is underlined, when it is handwritten.
  • The first term of the biological name begins with a capital letter. The second and the subsequent terms begin with the small letter.                  

           Codes for Biological Nomenclature    

      
             codes of nomenclature which helps to avoid errors, duplication and ambiguity in scientific names.

                                      These codes are as follows

                   I
CBN    INTERNATIONAL CODE OF BOTANICAL NOMENCLATURE
      ICZN    INTERNATIONAL CODE OF ZOOLOGICAL NOMENCLATURE
      ICVN    INTERNATIONAL CODE OF VIRAL NOMENCLATURE
      ICBN    INTERNATIONAL CODE OF BACTERIOLOGICAL NOMENCLATURE
      ICNCP INTERNATIONAL CODE OF NOMENCLATURE FOR CULTIVATED
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Commonly used modern drugs derived from plant sources: (Biodiversity Notes)

Commonly used modern drugs derived from plant sources:  DRUG                        PLANT SOURCE                                   USE
Modern drugs & their plant source
Commonly used modern drugs derived from plant sources:

 DRUG                        PLANT SOURCE                                   USE


1. Atropine                       Belladonna                  Anticholinergic: reduces intestinal pain in diarrhoe

2. Bromelain                    Pineapple                        Controls tissue inflammation due to infection.

3. Caffeine                       Tea, Coffee                     Stimulant of the central nervous system         

4. Camphor                      Camphor tree                  Rebefacient: increases local blood supply.

5. Cocaine                        Cocoa                             Analgesic and local anesthetic: reduces pain

6. Codeine                        Opium poppy                 Analgesic: reduces pain.

7.  Morphine                    Opium poppy                 Analgesic: controls pain.

8. Colchicine                   Autumn crocus               Anticancer agent.

9. Digitoxin                     Common foxglove         Cardiac stimulant used in heart diseases. 

10. Diosgenin                   Wild yams                     Source of female contraceptive: prevents pregnancy

11. Monocrotaline           Cotolaria sessiliflora      Anticancer agent.

12. Papain                        Papaya                           Dissolves excess protein and mucus, during                                                                                              digestion. 
13. Penicillin                   Penicillium fungi           General antibiotic, skills bacteria and controls                                                                                           infection by various micro-organisms.

14. Quinine                    Yellow cinochona            Antimalarial.

15. Reserpine                 Indian snakeroot              Reduces high blood pressure.
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Monday, June 11, 2018

Quiz on Environmental Issues

Environmental science

Multiple Choice Questions on Environmental Issues;Questions on Environmental Issues: MCQs ( Multiple Choice Questions) in Quiz Format
  1. Harmful trace metals in fly ash

  2. antimony
    cadmium
    arsenic
    all of the above

  3. The range of normal human hearing is in the range of

  4. 10 Hz to 80 Hz
    50 Hz to 80 Hz
    50Hz to 15000 Hz
    15000 Hz and above

  5. Algal bloom results in

  6. Biomagnification
    Global warming
    Salination
    Eutrophication

  7. The main atmospheric layer near the surface of earth is

  8. stratospere
    mesophere
    ionosphere
    troposphere

  9. Chipco movement is a public agitation that occurred in

  10. Mansbal area in Kashmir
    Silent valley in Kerala
    Sundarban area in Bengal
    Tehri Garhwal area of Uttar Pradesh

  11. High biological oxygen demand indicates

  12. absence of microbial pollution
    intense level of microbial pollution
    moderate microbial pollution
    All of these

  13. Example of primary pollutant

  14. hydrocarbon
    CO
    NO2
    SO2

  15. Drinking of fluoride containing water results

  16. fluorosis
    chlorosis
    minemata
    methaemoglobinema

  17. Which metal is the main air pollutant in metro cities?

  18. Lead
    Copper
    Magnesium
    Iron

  19. Carbon mono oxide is a pollutant because

  20. it reacts with O2
    reacts with haemoglobin
    makes nervous system inactive
    It inhibits glycolysis

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Sunday, June 10, 2018

10 True/False Questions on Ecology

Ecology T/F

True- False types of questions on the topic of ecology.
  1. Darwin’s concept about evolution occurring by natural selection is a law in ecology and evolutiona

  2. True
    False

  3. Statistics are used by scientists to prove hypotheses.

  4. True
    False

  5. Epistomology is the ecology of ecosystems and communities

  6. True
    False

  7. The ecology of a single species is called autotrophy.

  8. True
    False

  9. There are two important processes in an ecosystem; energy flows and nutrient cycles.

  10. False
    True

  11. Ecosystems vary in size.

  12. True
    False

  13. The birth rate of a population of lions is 0.5 and the growth rate is 0.2. What is the death rate?

  14. True
    False

  15. If one part of an ecosystem is altered then the whole ecosystem will be affected.

  16. True
    False

  17. Nutrients can be lost from an ecosystem through leaching.

  18. False
    True

  19. Where is most of the phosphorous stored in an ecosystem? -> In the ground

  20. True
    False

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Wednesday, June 6, 2018

Biodiversity Quiz 3

Biodiversity

TEN QUESTIONS ABOUT NATIONAL PARKS OF INDIA
  1. National Wildlife Protection Act was formulated during the year

  2. 1972
    1976
    1978
    1974

  3. Kanha National Park is famous For

  4. Birds
    Tigers
    Crocodiles
    Rhino

  5. Bandipur in Karnataka is the site for

  6. Project elephant
    Project Tiger
    Project Hangul
    None of these

  7. Periyar sanctuary is famous for

  8. Wild bears
    Wild Buffaloes
    Elephants
    Swamp deers

  9. In Which States is the Kanha National Park

  10. Rajasthan
    Madhya pradesh
    Uttar Pradesh
    Assam

  11. First National Park of India

  12. Jim corbett
    Periyar
    Palamau
    Kaziranga

  13. Jim National Corbett National Park is famous for.

  14. Tigers
    Rhino
    Lions
    Black Bucks

  15. The species of animal protected in Kaziranga sanctuary is

  16. Panthera leo
    Macaca mulatta
    Panthera tigris
    Rhinoceros unicornis

  17. Asiatic Lion is Found in

  18. Gir Forest
    Jim Corbett
    Kaziranga
    Sunderban

  19. Which one of the following bird is endangered

  20. Kite
    Parrot
    Horn bill
    Pigeons

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Monday, June 4, 2018

RELATIONSHIP BETWEEN SPECIES DIVERSITY AND ECOSYSTEM


RELATIONSHIP BETWEEN SPECIES DIVERSITY AND ECOSYSTEM


Most of the ecologists believe that
·         The communities with more species are more stable than those with lesser species.
·         The stable community means lesser variations in productivity from year to year.
·         The community with more species, is more resistant to occasional (natural or man-made) disturbances.
·         Such communities are resistant to invasions by alien or exotic species.
David Tilman, in his long-term ecosystem experiments, found that plots with more species showed less - year to year variation in   total biomass   and the increased diversity contributed to higher productivity.                                                                                                                          Thus the rich biodiversity is not only essential for the health of the ecosystem but also for the survival of human race on this planet.

Loss of Biodiversity

There is continuous loss of the earth' treasure of species. For example, the colonization of tropical pacific Islands by human has led to extinction of more than 2000 species of native birds.
The Red list of lUCN documented the extinction of 784 species in last 500 years. The last 20 years witnessed the disappearance of 27 species.
Some important examples of recent extinctions are
    Dodu (Mauritius), Quagga (Africa), Thylacine (Australia). Steller Sea-cow (Russia), and  subspecies of Tiger, like bali, javan and caspian.
·         Presently, more than 15,500 species world-wide are facing the threat of extinction.
·         This includes 32% of amphibian species, 23% of mammalian species and l2% of birds’ species.
·         About 31% of the gymnosperms species are also facing the extinction. The amphibians are however,more vulnerable in such cases.
From origin to evolution of life on earth, i.e. duration about 3 billion yrs., there have been 5-episodes of mass extinction, but the present, the 6‘*‘, mass extinction is 100 to l000 times fasterthan the pre-human extinctions.
The ecologists now warn that-in next l00 years about 50% of all the species on earth will be wiped out. The loss in biodiversity of a region leads to
1. Lowered resistance to environmental changes
2. Decline in the plant production
3, Increased variability in certain ecosystem, pest disease cycles and water use etc.

Causes of loss of Biodiversity

The accelerated rate of species-extinction is largely due to human activities. There are 4-major causes, called ‘The Evil Quartet’, for the loss of biodiversity -
l. Habitat loss and fragmentation
2. Overexploitation
3. Invasion of Alien or exotic species
4. Co-extinctions
·         Habitat loss and fragmentation
The cutting trees and burning of forest destroys the natural habitat of a species. The construction of mines, dams, harbors, industries and buildings for human settlement has also affected the biodiversity. The Habitat destruction is the primary and major reason for the loss of biodiversity.
The tropical rain forest is the example of the habitat loss where forest covering has been reduced from 14% of land surface to 6%.
The Amazon rain forest, called ‘The Lungs of the Planet ', which harbors millions of species, is being cleared for cultivating soybean or developing grasslands for raising cattle. The pollution is also the factor for degradation of habitat.
When large habitats are broken into small fragments due to various human activities, the population of migratory animals, mammals and birds, that require a large territory, are adversely affected.
·         Overexploitation
In ecology, overexploitation describes one of the five main activities threatening global biodiversity. Overexploitation can lead to resource destruction, including extinctions. Many marine fishes are also being over harvested. Over fishing from a water body, or over harvesting a product is
just like ‘killing a goose laying golden eggs '.
.
·         Invasion of Alien or exotic species
When alien species are introduced into an explored area, some of the species turn invasive and cause decline or extinction of indigenous species.
For example –
                       Introduction of Nile perch into lake Victoria (E. Africa) led to the extinction of more than 200 species of Cichlid fish in the lake
Introduction of weed species, like Carrot grass (Parrhenium), Lantana and water hyacinth (Eicchornia) has posed threat to the native species  and   damage to environment.
 The illegal introduction of African cat fish (Clarias gariepinus) for aquaculture purposes into the river has threatened indigenous cat fishes.
·         Co-extinctions
Whenever a plant or animal species becomes extinct, its obligatory-associated species also becomes extinct. For example, when a host species becomes extinct, the parasite also meets the same fate. In case of ‘plant pollinator mutualism ' the extinction of one species leads to the extinction of the other.

Process of extinction of biodiversity


1. Natural extinction -
With the change of environmental conditions some species have disappeared and the more adaptive species have appeared. This  extinction is slow and is called ‘Background extinction’.

2. Mass extinction –
lt is extinction of large number of species due to natural calamities/catastrophes. The extinction of Dinosaurs is one such example.

3. Anthropogenic extinction -
It is the disappearance of species due to human activities. This man-made extinction represents a severe depletion of biodiversity in terms of time. The current rate of extinction is thousand times higher than the background extinction.
If the current rate of losses continues the earth may lose up to 50% of the species by the end of 2 l “Century.
   

Susceptilibility to extinction -


The species with the following features are more susceptible (vulnerable) to extinction than the other species.

l. Larger body size (eg. Elephant, Bengal Tiger and Lion etc.)

2. Smaller population with low reproductive rate (eg. Blue whale and Giant panda)

3. Fixed habitat or migratory routes (eg. Whooping cranes and Blue whales).

4. Feeding at higher trophic level in the food chain, (eg. Bengal tiger and Bald Eagle).

5. Narrow range of distribution (eg. Island species and woodland caribou).



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Sunday, June 3, 2018

Biodiversity Quiz 2

Biodiversity Quiz

  1. What is Biodiversity ?

  2. A type of coconut
    A brand of oil
    The spread of all living things
    A plant species

  3. How many bio-geographical regions are present in India?

  4. 3
    6
    7
    10

  5. Lime is added to the soil which is too

  6. Sandy
    Salty
    Acidic
    Basic

  7. Biodiversity can be broadly classified into how many types?

  8. 2
    3
    4
    1

  9. Biodiversity is of importance as it offers:

  10. Stability of ecosystems
    Stability of species
    Stability of research
    Stability of atmosphere

  11. Causes of extinction of species:

  12. Introduction of exotic species
    Habitat destruction
    Over exploitation
    All of these

  13. Which is an extinct species?

  14. Dodo of Mauritius
    Kiwi from New Zealand
    Cheetah from India
    Both b and c

  15. Biodiversity has an aesthetic value to it.

  16. True
    False

  17. The area of National Parks range between:

  18. 0.61 to 7818 kms
    0.04 to 3162 kms
    0.14 to 3612 kms
    0.16 to 8718 kms

  19. Which group of vertebrates comprises the highest number of endangered species?

  20. Fishes
    Mammals
    Birds
    Reptile

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Friday, June 1, 2018

Pattern of Biodiversity

Pattern of Biodiversity

Biodiversity varies with the change of altitude and latitude.
·         The species diversity Is maximum in plants (low altitude) and equator (low latitude).
As we move from lower to Higher latitude (from equator to poles) or from lower to higher altitude, the biological diversity Decrease. The diversity also depends upon seasonal variability and physical environment like temperature, humidity etc.
Thus the diversity of animals and plants is not uniform throughout the world and shows uneven patterns.
 There 2 specific patterns of biodiversity

1.       Latitudinal pattern  The species diversity is the maximum at equator and decrease as move towards poles.

Image showing latitudinal pattern
The tropical diversity is highest between latitudinal ranges of 23.5°N to 23.5"S.
For Example
·         Columbia near) equator, has about 1400 species of birds,

·         while New York (41N) and Greenland (71°N) have 105 and 56 species only.

·         A forest of tropical regions, like Ecuador, has ten times more species of vascular plants as in the forest of temperate region, like mid-west USA.

·         Amazon rain forest of, S. America, has tl1e greatest biodiversity on earthAnd has about 30.000 species of fishes, 1300 species of birds, about 400 each of amphibians,
Reptiles and mammals, and 1,25,000 species of invertebrates. There are about 2 million species of insects and about 40,000 species of plants.


Graph of distribution of species in altitude vs latitude

 2.       Altitudinal Gradient The impact of altitude is significant on type of biodiversity. Mostly the increasing altitude leads to decrease in only biodiversity as only some species can adapt the conditions prevailing at high altitude.



 Following graph gives the clear idea this relationship




3.        Species -Area relationship


Species - Area relationship graph

The German naturalist and geographer, Alexander Von Humboldt, while exploring SouthAmerican jungles, observed that species - richness increased with increasing explored area, but only up to a limit.
This relationship between species richness and explored area is a rectangular hyperbola described by the equation - S = C Az
       Where  
             S             is    species richness                                  
                 C            is     Y-intercept                                                                                                                              A             is     area and                                                                                                                                     z    is the slope to the line ( regression coefficient). .                                                                                                                                                                         
On logarithmic scale, the relationship is a straight line, described by the equation -    Log S=Log C+Z log A
Ecologist have discovered that value of ‘Z’ always lies in the range of 0.1 to 0.2, irrespective of the taxonomic group (angiosperms, fish or bird), or the region /geographical area.  
But if we consider a large area (i.e., whole continent) , the Z-value in the range of 0.6 to 1.2)
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Pattern of Biodiversity Biodiversity varies with the change of altitude and latitude. ·           The species diversity Is maximum...

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