Race and Racism

Race is a concept. All men living today belong to a single species, Homo sapiens, which includes different groups or populations, each differing from other populations in the relative commonness of certain hereditary traits. each of these population constituting the species Homo sapiens may be regarded as a Race. National, religious, cultural and geographical groups […]

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Biological basis of morphological variation of non metric and metric characters.

1.Skin color: Basically three shades of skin color are seen in man 1.Leucoderms or white skinned people-europeans, west asians, north africans and polynesians,where color varies from pinkish white to tawny white or light brown. Within this group the brown skinned peoples like hamites,indo-dravidians etc. are also included. 2.Xanthoderms or yellow skinned people- Asiatic mongloids are […]

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Klinefelter(XXY), Turner(XO), Super female(XXX), intersex and other syndromic disorders

Sex chromosomal aberrations: Klinefelter(XXY), Turner(XO), Super female(XXX), Intersex and other syndromic disorders. Klinefelter(XXY): Non disjunction(the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei)produces extra sex chromosomes;one would also expect trisomy of the sex […]

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Numerical and Structural Aberration.

Chromosomes and chromosomal aberrations in man, Methodology. a)numerical and structural aberrations(disorders). Numerical abnormality can involve the loss and gain of a whole chromosome or chromosomes and can include both autosome and sex chromosome. Generally chromosome loss has a greater effect on the individual than the chromosome gain although these have also severe consequences. cells which […]

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Genetic imprints

Genetic imprints in human disease, genetic screening, genetic counseling, human DNA profiling, gene mapping and genome study. Genetic imprints in human disease: Principle of equivalence given by Mendal states that the gene for tallness from whichever parent is derived ,expresses in the offspring always the same way,however,it does not apply in case of gene imprinting. […]

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Autosomal aberrations: Down syndrome, Patau, Edward and Cri-du-chat syndrome.

Down’s syndrome: Down syndrome results from aneuploidy – trisomy21. Hence the person with down syndrome has 47 instead of 46 chromosomes because of the presence of one extra chromosome number 21. represented as (47,+21).also called mongloid idiocy or mongolism because individuals with trisomy 21 were considered to have some certain facial characteristics that resembled oriental […]

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Concept of genetic Polymorphism

Concept of genetic Polymorphism and selection, Mendelian population, Hardy-Weinberg law: causes and changes which bring down frequency-mutation, isolation, migration, selection, inbreeding and genetic drift. Consanguineous and non-consanguineous mating, genetic load, genetic effect of consanguineous and cousin marriages. Genetic Polymorphism: the populations which are characterized by individuals with discrete, discontinuous genetic traits are said to be […]

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Cytogenetic method, Chromosomal and Karyotype analysis

Cytogenetic Method: Cytogenesis is the study of chromosomes and the related diseases states caused by abnormal chromosome number or structure. The basic mathod of obtaining chromosome preparation is-simple log in and initial setup-tissue culture(feeding and maintaining cell culture)-addition of a mitotic inhibitor to arrest cells at metaphase. Chromosomal and karyotype analysis: Karyotyping is the analysis […]

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