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 Biology project HSC All Chapters answers Download for Pdf  Sr. No.   Name of experiment        A. List of experiments to be performed     1   Study of osmosis by potato osmoscope.     2   Study of plasmolysis in epidermal peels.     3   Study of structure and distribution of stomata on upper and lower surfaces of the leaf.     4   Study of pollen germination on the slide.     5   Study of soil samples at least from two different localities/ sites with respect to their texture and pH and correlate plants found thereof.     6   Study of suspended particulate matter in the air at the two widely different sites, in your area.   7    Study of water samples collected from different water bodies for their pH, clarity, and presence of living organisms (microscopic/ planktonic).

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 5. Study of V. S. of anatropous ovule through a permanent slide / relevant chart.   Ovule (megasporangium) is enclosed in the ovary.   There may be one or many ovules in an ovary.   Alm:  Study of anatropous ovule and functions of its various parts.  .  The ovule in which micropyle, chalaza, and funicle are not in one straight line and integuments run parallel to funicle is called as anatropous ovule.  It is also called an inverted ovule and is the most common type of ovule, in angiosperms, The ovule shows two main parts - body and funicle.  Body The body shows two integuments originating from the base of the ovule reaching up to the tip of the ovule.   The tip shows a small cleft, left by two integuments called a micropyle.  The integuments enclose a mass of fertile, parenchymatous, diploid cells called nucellus.  There is only one fertile cell loc

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 2. Separation of plant (photosynthetic) pigments by paper chromatography Aim:  Separation of plant (photosynthetic) pigments by paper chromatography.  The plants show the presence of many pigments.  The different photosynthetic pigments present in the leaf cells are chlorophylls, carotenes, and xanthophylls.  These photosynthetic pigments can be separated using the technique of paper chromatography.  Principle The separation of solutes (chloroplast pigments) is based on the liquid-liquid partitioning of pigments in paper chromatography.  The partitioning takes place between the solvent (water) molecules (static phase) adsorbed to the cellulosic matter of the paper (capillary action organic (mobile) phase.)  Requirements -  Chromatography chamber, chromatography paper (Whatman's filter no.1), pestle - mortar, capillary tube, muslin cloth, suitabl

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF B. DEMONSTRATION EXPERIMENTS 1. Comparative study of rates of transpiration in the upper and lower surfaces of the leaf, using four-leaf experiment.  7 Loss of excess water in the form of vapor through the aerial parts of the plant is called transpiration.  Aim: To study the comparative rate of transpiration in the upper and lower surfaces of a leaf by conducting four-leaf experiments.   Requirements: -  Two stands, thread, four leaves of Calotropis / banyan tree, Vaseline (petroleum jelly), etc.  Fig.  Comparison of transpiration, a demonstration by four-leaf experiment Apply Vaseline to leaf surface in the following manner,  1. Leaf A: - Petroleum jelly is applied on both surfaces  Figure: Procedure:  The leaves selected should be healthy preferably of the same size and showing growth.  Tie the different leaves of the same plant with thread in suc

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 1. To detect the presence of starch added as an adulterant to the milk.   A Biter-proof starch added adulterants to the milk.  come animal source cow/buffalo), etc.  The pipettes,  1 iodine solution, milk samples (minimum 3, preferably will They Addition of much increases the SNF (Solid Not Fat) content of milk. Wheat flour, I flour can be added for increasing the SNF (Solid Not Fat) content.  Starch proper synthetic milk, which is, then added to natural milk. This is commonly used opposite for the added water. Since the starch powder is easily and cheaply available, it is the adulterant to milk, after water. Procedure Measure out 3ml milk into a  test tube/container.  2. Keep the test tube for incubation in a boiling water bath for 5 minutes.  3. After incubation, cool the test tube, add a few (2-3) drops of 1% iodine solution and mix the contents

  Practical Notebook Biology Standard XII Biology  Answered. Practical Notebook Standard XII Class-12th science Click here download in PDF 12. To examine the presence or absence of Barr body in the given sample.   Alm:  To observe Barr bodies in squamous epithelial cells obtained from the inner lining of the check (Buccal smear).  Requirements: Cotton buds, slide saline solution, 70% alcohol, Giemsa / Methylene blue stain compound microscope, etc  Procedure:  Clean the mouth by rinsing and gargling with water, several times.   Take a sterile cotton bud and in normal saline solution   Rub it on the inner lining of the cheek several times.   Smear the bud on a clean slide and allow it to dry.   Place the slide in a Petri dish.  Layer it with a fixative (70% alcohol).    Allow it to stand for a few minutes.    Drain off the extra fixative.    Stain the smear with Giemsa / Methylene Blue and wait for 10 minutes.    With the help of a dropper gently wash off the excess stain with water.  

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 9. Isolation of DNA from Given Sample  Aim:  To extract and isolate DNA from a fruit sample.   Requirements: -  Fleshy berry fruits like banana, Zizyphus, grapes, etc, can be used.  Fleshy fruits of banana, liquid soap, distilled water, salt (NaCl), 1000 ml ice-cold isopropyl alcohol i.e.  IPA (Chill the alcohol (IPA) by placing the test tube in a beaker containing ice cubes and some water] measuring spoons, glass stirring rod, test tubes, glass beakers, plastic cups, strainer or coffee filter, funnel, etc. Principle:  All plants' DNA extraction protocols comprise the basic steps of disruption of a cell wall, cell membrane, and nuclear membrane to release the DNA into solution followed by precipitation of DNA and ensuring removal of the contaminating biomolecules.  A figure is separated by physical means such as grinding,  to form a mash  The ce

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 10. Dissect and display floral whorls.  Dissect another and take T.S.  or V.S.  of the ovary to show pollen grains and locules of the ovary, respectively.    Aim:  To dissect given flowers to study and display different whorls.  Dissect anther and ovary to show a number of locules (chambers).   Requirements: -  Flowers such as Brassica or Hibiscus.  Forceps, razor blade, slides, two needles, coverslips, dissecting microscope, paper, etc.  Ced  Procedure: -  Observe different floral whorls such as calyx, corolla, androecium, and gynoecium.  Take out each floral whorl carefully and arrange them in proper ascending order on white paper.  Count the members of each whorl and also note down, if there is cohesion or adhesion between the members of the same whorl or different whorls.  Mount the anthers on the slide and observe them under a lens or dissectin