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Introduction to Chitwan National Park

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National Parks, Conservation Area and Wildlife Reserves of Nepal


 Chapter-1

Chitwan national Park
Chitwan National Park, the oldest national park in Nepal, is situated in the subtropical inner Terai lowlands of south-central Nepal. It covers 932 square kilometers. It offers a wilderness of rich ecosystem that includes mammals, birds, reptiles and water animals of several kinds. The park was declared UNESCO Heritage Site in 1979 owing to its rich adornment of nature. The park covers a pristine area with a unique ecosystem of significant value to the world. It contains the Churiya hills, Ox-bow lakes and flood plains of Rapti, Reu and Narayani Rivers. There are around 600 plant species, 50 mammals, 526 birds and 49 amphibians, reptiles found in the park.

The park is specially renowned for the endangered one-horned rhinoceros, the tiger and the gharial crocodile along with many other common species such as gaur, wild elephant, four-horned antclope, striped hyena, pangolin, Gangetic, dolphin, monitor lizard and Python. Other animals found in the park include the sambar, Chital, Hog deer, Barking dear, Sloth Bear, Palm civet, Langur and Rhesus monkey. The forest is alive during summer with the arrival of migrant birds, paradise flycatcher, Indian pitta and parakeets, which winter birds include Waterfowl, Barminy ducks, Pintails, Bar-headed geese, Cormorants and migratory birds from Siberia. A rare attraction of the park is the world's fresh water dolphin variety sometimes seen in River Narayani. The park is being the centre of scientific studies of several species of wild flora and fauna.It is famous for one horned rhinoceros and Wild Buffaloes. Spiny Babbler , the only bird found in Nepal is also probably found in it.

Origin and Evolution of Life

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Life and its Origin
Life is a unique and complex phenomenon that distinguishes the living organisms from non-living things or inanimate things. The origin of life in the universe is one of the most complicated problems for the biologists. The problem of creation resolves itself into two aspects: the origin of the forms of life and origin of life itself. Different biologists have proposed different theories concerning the origin of life. The major theories accounting for the origin of life are:

    •  Life was created by a supernatural power at a particular time (Special Creation Theory
    •  Life arose from non-living matter on numerous occasions by a process of spontaneous generation (Theory of Spontaneous Generation) 
    •  Life has no origin (Theory of Eternity of Present Condition)
    •  Life arrived on this planet from elsewhere (Cosmozoan Theory)
    •  Life arose according to chemical and physical laws (Biochemical Evolution)

      Alexander Oparin-Theory of the origin of life

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      Born :     March 2, 1894
      Citizenship :     Soviet Union
      Died :    21-April, 1980
      Nationality :    Russian
      Institutions :    Moscow State University USSR Academy of Sciences
      Known for  :   Contributions to the theory of the origin of life coacervates
      Fields :    Biochemistry

      Notable awards :    Hero of Socialist Labour (1969)
      Kalinga Prize (1976)
      Lenin Prize (1974)
      Lomonosov Gold Medal (1979)

      Biochemical Theory of Origin of Life

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      This theory was proposed by two scientists. Alexander Ivanovich Oparin (1923) and J.B.S. Haldane (1928) independently. They stated that the origin of life occured along with the origin and evolution of Earth and its atmosphere. The origin of Life occured from non-living simple molecules, simple molecules formed simple organic compounds, simple organic compounds formed complex organic compounds which then gave rise to the first living cell or pre-cell. This theory is called Oparin-Haldane Theory.

      The above life process can be explained in three steps-

      Chemogeny(Chemical Evolution)
      • Formation of Simple Molecules
      • Formation of Simple Organic Compounds
      • Formation of Complex Organic Compounds 
       Biogeny(Biological Evolution)
      • Formation of Coacervates
      • Formation of Primitive Life
       Cognogeny(Modification of Life)
      • Origin of Heterotrophs
      •  Modification of Heterotrophs into Autotrophs

      English natural philosopher-Robert Hooke

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      Robert Hooke
      Robert Hooke
      Architect
      Robert Hooke was an architect, Natural philosopher and polymath. His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing .
      Born: 28-July, 1635, (UK)United Kingdom
      Died: 3-March, 1703, (UK)London,
      Nationality: English
      Books: Micrographia, more
      Education: Oxford, Wadham College, Christ Church, Westminster School, Oxford, University of Oxford

      Question Bank of Microscope

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      Question Bank of Microscope
      1. What is Microscope?
      Ans: A microscope is an instrument used to magnify small objects that cannot be seen by naked eye.
      2. How many times does a compound microscope magnify?
      Ans : Magnifying power of a compound is equal to the magnifying power of the objective lens into the magnifying power of eyepiece. It varies from 100 times to 600 times or more.
      3. Name the optical parts of a compound microscope.
      Ans: Eye piece, objective lens and plano-concave mirror.
      4. How is object magnified in compound microscope?
      Ans: The power of eye piece and objective lens magnify the object.
      5. Why observed the cells for the first time under the microscope?
      Ans: Robert Hooke.

      Handling of Compound Microscope

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      Handling of Compound Microscope
      1. Place the microscope on the table by holding the arm at the back with one hand and base with other hand
      2. Fix the lower power objective and adjust the mirror so that light may pass through the objective. When you see a bright round space then you should be sure that light is passing properly through the stage to the objective.
      3. Gently place a slide with the specimen over the stage. Use clips to hold the slide firmly.
      4. Look through the eye-piece and adjust with the help of course adjustment until the object comes in view.
      5. Now focus an object fine and sharp with the help of fine adjustment.

      Magnification of Object

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      Magnification of Object

      A microscope magnifies an object in two stages. The lens system magnifies the object the 5 to 100 times depending on the power of the objective lens. The ocular lens magnifies an object 5 to 15 times. The individual magnification poser of the ocular or objective is written on the outside of its barrel. To calculate the total magnification the image with each objective, use the following equation:
      Total magnification = Magnification of obbjective lens × Magnification of eye piece.
      Handling of Compound Microscope

      Optical parts of a Compound Microscope

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       Optical parts of a Compound Microscope
      1. Mirror: It is a plano-concave mirror, with one side plane and other concave. It is attached to the lower end of the arm. It is used for reflecting light rays into the microscope. The plane mirror is used to reflect the rays of light coming from nearby sources such as a bulb or a tube light while the concave mirror is used to reflect the rays of light from distant source i.e., the diffused sunlight.
      2. Objective lenses: They are attached to the nose piece. Generally the lenses with the magnificating power of 5x, 10x, 40x and 100x are available. These lenses magnify the image of the object by the number written on the lens.
      3. Eye piece lens: It is also called ocular lens and attached to the top of the body tube. It normally ranges in magnification from 5x, 10x and 15x. It is used to magnify the image produced by the objective.
      Magnification of Object

      Study of Microscopes

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      A compound microscope is a delicate optical instrument consisting of two-lens system (eye piece and objective lens) that magnifies the minute transparent or translucent objects manifold in two steps and enables us to study their minute details. This two- fold magnification is the principle behind the working of the compound microscope. The compound monocular microscope consists of many parts, which are assembled to either mechanical parts or optical parts.
      Machanical Parts of a Compound Microscope:
      1. Foot: it is usually a horse- shoe shaped lowermost part. It supports the weight of the microscop.
      2. Pillar: It is a small vertical stand attached to the base. It supports the movable parts.
      3. Inclination joint: It is a pivot between the pillar and the arm. It permits the tilting of the upper part of the compound microscope at various angles.
      4. Arm: It is a curved part of a microscope and its lower end is attached to the pillar and the upper end is joined to the body tube. It is used for handling.
      5. Condenser: It is a circular chamber with lens system, present below the stage that can be raised or lowered. It is used to concentrate the light rays.
      6. Iris diaphragm: It is a circular piece with a knob below the condenser. The left and right movements of the knob control the amount of light entering into the microscope on the object.
      7. Stage: It is usually a rectangular platform having a circular hole in the center to allow the light to pass through. It is used for keeping an object to be magnified.
      8. Clip: There are two clips attached to the stage, one on each side. These are used for holding the glass slide onto the stage firmly.
      Optical parts of a Compound Microscope

      Mountain Technique

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      Mounting is necessary to properly position an object for clear view. It is the last step in the process of slide preparation. For mounting, put a drop of suitable mounting medium such as water or glycerine or canada balsam on the center of a clean glass slide. Place the material on the mounting material with the help of a fine brush or forceps and finally place a clean cover slip on it. To place the cover slip properly, hold the cover slip with the forefinger and the thumb of the left hand and support it by a needle hold in the right hand. Lower down the cover slip slowly and touch one edge of the cover slip obliquely on one side of the mounting liquid. Holding the other edge of the cover slip with a needle point lower it down slowly to avoid air bubbles till it completely touches the slide. Suck the excess fluid outside the cover slip with the blotting paper.
      The slide which is without any air bubble is considered as the good slide. Therefore, try to avoid the entrance of any air bubble.

      Technique of free-hand section cutting

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      The first step of slide preparation is section cutting. Keep all the requirements needed for section cutting such as watch glass, sharp razor or safety blade, slide, brush, needles, water and materials in front of you. Hold the material vertically in between the thumb and fore fingure of the left hand in such a way that the material lies at the level of fore finger and the thumb below it. hold the razor or blade by the right hand, now, make a horizontal cut to material with a single stroke. Repeat the process several times by moving the blade rapidly so as to get a number of sections. Keep all the sections collected on the blade on water
      into the watch glass. Select a number of thin and uniform sections and place them on the slide with the help of a fine brush. Select under microscope the best thin and unruptured sections from them. Discard the thick, incomplete and oblique sections.

      Preparation of different types of mount

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      Biology
      Wet Mount (WM)
      It is the most common type of slide preparation. It is used when the object or material is observed immediately within few minutes after the preparation. This type of mount can't be kept for even an hour. For this type of slide water is used. Put 1 or 2 drops of water on the center of a glass slide. Transfer the material with the help of brush or a forceps and place on the water. Apply the conver slip and remove the excess water along the edge of cover slip with a blotting paper or with a piece of cotton/cloth.
      As the water is used as mounting medium, the preparation will get dry very soon due to evaporation. Therefore, the observation should be carred immediatelly after the perparation.
      Temporary Mount
      It is also common type of slide preparation. It is used when the object or material is observed for few hours after preparation. It can be kept for few hours. For this type of slide glycerine is used instead of water.
      Put one drop of glycerine on the center of a glass slide. Take material with the help of brush or a forceps and place on glass slide. Apply the cover slip over mounting material. Remove excess glycerine using a blotting paper.
      Whole Mount (WM)
      In this type of slide preparation, eatire organism is studied. Put one drop of mounting material (Water of glycerine or canada balsam) and transfer the stained or unstained materials on it. Remove excess glycerine with a blotting paper. Whole mount is commonly made for the observation of smaller organisms such as unicellular organisms and thin thalloid materials.
      Permanent Mount
      This type of slide is prepared when the meterial is preserved for long time. It is essential to reove out the water from the materials. The process is called dehydration process. Therefore, the material is required to pass through different concentrations of alcohol (10%, 30%, 50%, 70%,90%,100%) for dehydration process, 
      Put one drop of mounting material canada balsam on a glass slide. Transfer the dehydrate material over the canada blasm and cover it with cover slip. In this way, permanent slide can be kept or stored for years.

      Technique of free-hand section cutting

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      Biology
       Technique of free-hand section cutting
      The first step of slide preparation is section cutting. Keep all the requirements needed for section cutting such as watch glass, sharp razor or safety blade, slide, brush, needles, water and materials in front of you. Hold the material vertically in between the thumb and fore finger of the left hand in such a way that the material lies at the level of fore finger and the thumb below it. hold the razor or blade by the right hand, now, make a horizontal cut to material with a single stroke. Repeat the process several times by moving the blade rapidly so as to get a number of sections. Keep all the sections collected on the blade on water into the watch glass. Select a number of thin and uniform sections and place them on the slide with the help of a fine brush. Select under microscope the best thin and unruptured sections from them. Discard the thick, incomplete and oblique sections.
      The material, which is very small or fragile to hold without support, pith is used to hold it. pith is a stiff tissue used to support the soft tissue during the section cutting. potato, carrot and radish are commonly used as the pith. Take a piece of pith (sized enough to hold by hand) and cut vertically down leaving a portion enough to hold the specimen. Place the material in between two haves of the pith and hold tightly. Now, follow the above mentioned methods of section cutting to cut the pith along with material horizontally.

      Laboratory Techniques

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      Biology
      Laboratory Techniques:
      1. Fixing agents and preservatives
      2. Section cutting
      3. Staining
      4. Dehydration
      5. Mounting
      Section Cutting
      When an internal tissue of anatomical structures of a particular organ is studied, a thin section of the concerned part is taken by freehand. The sections are cut in various planes:
      1. Transverse section (T.S.)
      2. Vertical section (V.S.)

      General Instructions to the Students

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       Biology
      1. Need of practical for the science students
      For the science students, practical is very important as they can verify any facts which they study in the theory classes. The students do the practical with their own hand. So that, they understand theory well.
      2. What is a laboratory?
      Laboratory is a place where the necessary apparatus and equipment are kept to perform a certain experiment for the teachers and the students.
      3. Assets to bring to the laboratory
      While coming to the lab for the practical purpose, students of biological group are required to bring necessary biological assets with them. 
      4. Proper care of instruments and equipments
      The insturments, apparatus, glassware and other materials must be carefully handled. Students should replace the apparatus back to the same position after use. Students must clean or maintain the apparatus before and after use.
      5. Punctuality and disclipline in the laboratory
      A science student must be punctual in the practiaal class to keep his practical record up to date. Once the practical class is missed, it is difficult for the teacher to repeat it. A student is required a high degree of discipline in the laboratory.
      6. Maintaining practical record :
       Biology practical record can be bought from the stationary. Practical paper must be of good quality. Students must maintain their practical record file up to date, neat and clean. The practical should be recorded in your file on the same day. Students must get the practical checked by the teacher.
      7. Drawing and labeling the diagrams
      Diagrams should always be made on clean biology practical sheets. Students must follow the given rules to draw and label the diagrams:
      8. Writing comments 
      After drawing a diagram students may use a separate ruled parer to write comments. Comments can be writen with pencil or pen. Comments are written in points. Students are advised to see and follow the sample shown by he instructor in the practical exam.
       
       

      Preparation of Some Usefule Reagents- Laboratory Protocal

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      Students' Biological Practical Assets
      While coming to the laboratory for the practical purpose, biological group students are required to bring certain necessary biological assets with them. The important assets are listed below:
      1. Practical record book (biological drawing comments sheets, a cover file and a binding lace)
      2. Manual of Practical Biology (A Text Book of Practical Biology -X1)
      3. Apron
      4. Pencils (HB)
      5. Pencial sharpener, eraser and scale
      6. Piece of cloth
      7. Blotting paper
      8. Disseeting set wiht following equipments:
      a. Scissors: 2: one fine and pointed, other large blunt
      b. Foreeps: 2:
      c. Dissecting needles: 2 (spear headed)
      d. Scalpels: 2: one small and one large
      e. Fine camel-hair brush: 1
      f. Blade: 1
      g. Dropper: 1
      h. Hand les: 1
      i. Razor: 1
      j. Magnifying lens (10X)
      Preparation of Some Useful Reagents

      Students' Biological Practical Assets - Laboratory Protocal

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      Students' Biological Practical Assets
      While coming to the laboratory for the practical purpose, biological group students are required to bring certain necessary biological assets with them. The important assets are listed below:
      1. Practical record book (biological drawing comments sheets, a cover file and a binding lace)
      2. Manual of Practical Biology (A Text Book of Practical Biology -X1)
      3. Apron
      4. Pencils (HB)
      5. Pencial sharpener, eraser and scale
      6. Piece of cloth
      7. Blotting paper
      8. Disseeting set wiht following equipments:
      a. Scissors: 2: one fine and pointed, other large blunt
      b. Foreeps: 2:
      c. Dissecting needles: 2 (spear headed)
      d. Scalpels: 2: one small and one large
      e. Fine camel-hair brush: 1
      f. Blade: 1
      g. Dropper: 1
      h. Hand les: 1
      i. Razor: 1
      j. Magnifying lens (10X)
      Preparation of Some Useful Reagents

      Importance of Practical Work- Laboratory Protocal

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      Importance of Practical Work
      Safety Rules
      1. Perform the laboratory experiments seriously.
      2. Before conduction experiments, students must know about the experiment and precautions to be cared.
      3. Do not play with any apparatus, microscope, razor, knife, etc.
      4. Never talk loudly and run around the lab. Be calm in the laboratory.
      5. For any damage or breakage, must inform to the lab incharge or instructor.
      6. Use hand gloves for dissection of animals and wash your hands with soap and dettol after dissection.
      7. In case of any accident, inform immediately to your instructor.
      8. Handle the glassware carefully. Do not eat or drink in the laboratory.
      Students' biological Practical Assets:

      Laboratory Protocal

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      Inportance of Practical Work
      Practical work is an es: ential part of a course in biology. It is a systematized study based on facts and observation. It helps to understand the theory and verify the facts by actual doing. It providers an opportunity to a student with scientific frame of mind to see and study various aspects of an object under observation. It also removes any doubts and miserliness and gives a critical appreciation of how the science of biology is carried out. Practical prepares the students to work systematically, scientifically and understand the concept of biological science in better way.
      Almost all the modern inventions and applications of science in daily life are the results of constant experimentation by the scientists and technicians. For the experiment, scientists need a well-equipped laboratory where they perform scientific experiments.

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