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  Practical Notebook Biology Standard XII Observe the prepared slide of a blood smear to identify different types of blood cells Project Download in Pdf Chapter 14 Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 14. Observe the prepared slide of the blood smear to identify different types of blood cells.  Aim:- To identify and observe the types of blood artis in freshly prepared blood smear. Requirements:- Blood sample slides, Lentoon's stain, compound microscope. Procedure  A Hoxed or used to say or only the types of Mood cells but also the To be able to see the different types of cells in the poravites, if any, in the Mood of Pla Mood, the hood Mr bod in other words layer on the slide This spread of Mood on a slide is called Smear  To observe all the cells present in the blood sample under the microscope, they must be stained appropriately.  This process is called Staining Various staining like Leithmon's stain or Wright's s

Practical Notebook Biology Standard XII Study of morphological adaptations of animals, fount=d in xeric and aquatic conditions or habitats Biology  Answeres Practical Notebook Standard XII Class-12th science 11. Study of morphological adaptations of animals, found in xeric and aquatic conditions or habitats.  Aim -  Study of two animals cach found in xeric (desert) and aquatic conditions (habitats) with respect to their morphological adaptations.   Desert animals show adaptations for the conservation of water and deal with extreme dual temperature fluctuations.  L. Camel (Camelus spp):.  It is a xerocoles animal adapted to the desert conditions.   It can tolerate wide range of temperature fluctuations.   • It excretes concentrated urine in order to conserve water.   • It accumulates fat in the hump so that heat flows away from the body and inward flow of heat is prevented.  L Camel can even close its nostrils to stop blowing sand from entering nostrils.   It is a two-toed ungulate show

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF To study the prepared pedigree charts of genetic trolling of the tongue, widow's peak, blood groups, and color blindness  Male Female Introduction:  A pedigree is a list of ancestors showing genetic relationships between members of a family.  A record of inheritance of certain genetic traits for two or more generations is presented in the form of a family tree or a diagram is called a pedigree chart.  The study of pedigree charts provides a strong tool, which is used to trace the inheritance of a specific trait, abnormality, or disease family.   In a pedigree charts specific that are used, are indicated below:  Mating symbols and children 1 bey I girl ( in order of beth ) Duygotic ( identical twin ) Monorygotic ( identical twins ) Sex unspecified OOD Number of children of sex indicated Affected individuals  Heterorypotes for autosomal recessive

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 9. Demonstration of hybridization technique  Introduction Hybridization is one of the methods of crop improvement undertaken to combine the and female parents.   The technique involves the following steps:  desired, useful characteristics from two different pure varieties of plant species, selected as male & Collection of pollen grains  (Anthesis): Pollen grains from the flower of the selected male parent are collected in sterile paper bags and are stored in clean and dry vials at a cool place.  The collection is done in the early hours of the morning.  Day, date, and time of Anthesis are recorded.  b.   Emasculation:  It is the removal of young anthers of the stamens in the plant selected as the female parent having bisexual flowers, well before anthesis i.e. formation of pollen grains.  The bisexual flower of a female parent is emasculated. Bu

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF 8. Study of plants found in xerophytic and aquatic conditions/habitats.  And comment on their adaptations  Introduction:  Adjustment (acclimatization) of plants and animals for their survival and perpetuation, to their environment by means of special structures or functions, is known as adaptation The plants that can grow and survive in deserts, dry conditions of soil, and high temperature, are called xerophytes.  All xerophytes show adaptations to reduce the loss of water due to transpiration.  Some xerophytes show the presence of stored mucilage in the plant parts that help in retaining water.  Some plants have latex, that helps retain water and seal the place of injury.  E.g.  Euphorbia, Calotropis, Acacia, Opuntia.   The plants that grow in abundance of water are, called hydrophytes.  They are generally adapted to remain buoyant and avoid the dec

  Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF https://drive.google.com/file/d/10NrtEg6k0Hh8ttkenvZvI2EzFqZN8vPr/view?usp=sharing 7. Study of meiosis in onion flower bud with the help of permanent slides.  Aim:  To study and identify different stages of meiosis.  Principle 1 Meiosis is a special type of cell division that occurs in the diploid reproductive or germ tissue (cells).  It is a reduction division that results in the formation of four haploid daughter cells each receiving half of the total number of chromosomes than those present in the mother cell from which it is produced Observation For the preparation of meiosis slides, generally, anther of Lily or Onion is used.  Meiosis can be studied with the help of stained permanent slides of T. S. of the anther.  Permanent slides should be observed under the high power of a compound microscope.  Meiosis is a process that occurs in two steps vi

Practical Notebook Biology Standard XII Biology  Answeres Practical Notebook Standard XII Class-12th science Click here download in PDF T.S.  Testis: Date Internal structure of testis shows the presence of tunica albuginea and seminiferous tubules.  Testis 6. Study of T. S. testis, T. S. ovary, and V. S. of blastula, through permanent slides.  Is externally covered by fibrous connective tissue called tunica albuginea.  It is internally covered by tunica vascularis formed by capillaries and externally by an incomplete covering called tunica vaginalis.  Seminiferous tubules are lined by cuboidal germinal epithelial cells.   It shows different stages of spermatogenesis lic spermatogonia, primary and secondary spermatocytes, spermatids, and sperms.  Few large pyramidal cells are present interrupting germinal epithelia are nurse cells or Sertoli cells.  Sperm bundles get attached to Sertoli cells with their heads.  The function of Sertoli cells is to provide nourishment to the sperms till