Anthropology 1001 Exam 1 Carl von Linne Better known as Carolus Linnaeus Linneaus was a creationist and an advocate of the Principle of Fixity of Species All species were created by God and species were immutable and unchangeable after their creation Jean Baptiste Lamarck Theory of Inheritance of Acquired Characteristics Use and Disuse 1 Organism has needs in order to survive 2 Needs are met by modification of organs or production of new organs 3 Continued use of an organ leads to an increase in its size and functional capacity whereas disuse leads to its degeneration and loss 4 Changes in an organ that occur during one s lifetime are inheritable and can be passed to one s offspring this is the one that invalidates his whole theory Georges Cuvier The most renowned anatomist of his day Theory of Catastrophism 1 In the past there were a series of sudden violent geological and climatic changes that led to the extinction of animals in the affected region After the cataclysm subsided the region was repopulated by animals from neighboring areas that were similar in appearance but not identical with those that went extinct Charles Lyell Theory of Uniformitarianism 1 Forces existing today that shape the earth are the same as those that acted in the past Thomas Malthus Essay on the Principle of Population Graph of food and population and how they relate Charles Darwin Theory of Natural Selections to explain transformation of a species over time Observations on Galapagos Islands Alfred Russell Wallace Also developed theory that species change by natural selection Charles Darwin s book On the Origin of Species was published in 1859 1 Reproductive potential of a population is great but actual population size remains stable 2 Resources in the environment are in limited supply there is competition among individuals for the resources same graph as Malthus 3 Biological variation is normal in a population 4 Any hereditary variation that allows an organism even a slight advantage in competition for resources will be preservedz Organisms with the favorable variations will survive and produce more offspring Over time there will be an increase in frequency of the favorable traits in the population End of species transformation material beginning of inheritance Gregor Mendel Published his paper on inheritance in 1866 No interest expressed in his results EX Seed Texture Round or wrinkled Parental Generation First Generation Second Generation Round X Wrinkled 100 Round Round X round self fertilization 75 Round 25 Wrinkled Round X round and wrinkled X wrinkled self fertilization l l l Third Generation 100 round 75 round 100 wrinkled 25 wrinkled Principle of Segregation Genes occur in pairs in an organism In the production of sex that pair of genes is separated Each sex cell contains one of these genes Round RR Wrinkled ww Gene segment of DNA that codes for a protein Allele alternative forms variants of the same gene Punnett Square Genotype a set of genes possessed by an individual Phenotype physical expression of the genotype Homozygous having two copies of the same allele either RR or ww Heterozygous having one copy of each of the different allele Rw Dominant Allele allele that is expressed phenotypically in both a homozygote and heterozygote Recessive Allele expressed phenotypically only in a homozygote not in a heterozygote Principle of Independent Assortment the segregation of one gene does not influence the segregation of other genes Each gene segregates independently from other genes 1 Seed texture Round or wrinkled R or w 2 Stem length Tall or short T or s RwTs X RwTs Phenotypes Round Tall 9 Round Short 3 Wrinkled Tall 3 Wrinkled Short 1 Traits Genotypes RRTT 1 RRTs 2 RWTT 2 RwTs 4 RRss 1 Rwss 2 wwTT 1 wwTs 2 wwss Cellular reproduction mitosis and meiosis Chromosomes are inside the nucleus which is inside the cytoplasm Mitosis 1 Non sex cells undergo mitosis 2 Functions a Growth of an organism b Maintenance of organs parent cell 3 Ultimate function of mitosis is to produce cells that are genetically identical to the Homologous chromosome same sequence of genes Chromatids identical chromosomes Centromere constricted part of the chromosome that holds two chromatids together Interphase FIND PICTURES 1 Genes are active 2 Chromosomes are duplicated and replicated Mitosis 1 Prophase nothing important 2 Metaphase a Chromosomes align independently from one another 3 Anaphase 4 Telophase Results of Mitosis a Centromeres divide 1 Two cells are produced each with the diploid chromosome Diploid Full complement of chromosomes 2 The daughter cells are genetically identical to the parent cell and with one another The ultimate function of mitosis is the production if daughter cells that are genetically identical with parent cell Meiosis 1 Sex cells are formed by meiosis 2 Function transmit an organism s chromosomes to one s offspring 3 The ultimate function of meiosis is the production of genetically variable sex cells 1 Meiosis Prophase 1 2 Meiosis Metaphase 1 Homologous chromosomes synapse crossing over recombination Homologous chromosomes remain paired non homologous chromosomes align independently from one another 3 Meiosis Anaphase 1 Centromeres do not divide 4 Meiosis Telophase 1 We now have 2 cells 5 Meiosis Prophase 1 Nothing important 6 Meiosis Metaphase II 7 Meiosis Anaphase II Centromeres divide 8 Meiosis Telophase II We now have 4 cells Chromosomes align independently from one another Synapse pairing of homologous chromosomes Crossing over recombination physical exchange of segment of a chromosome between homologous chromosomes Haploid half of the chromosome number half of the diploid Results of Meiosis 1 Four cells are produced each with the haploid chromosome number 2 The daughter cells are genetically different from the parent cell and from each other 3 Ultimate function production of genetically variable sex cells Differences between Meiosis and Mitosis 1 Number of daughter cells produced 2 Chromosome number in daughter cells 3 Genetic structure of daughter to parent cell and to one another 4 Functional result Mitosis 2 diploid identical exact duplication Meiosis 4 haploid different virtually infinite genetic variability Replication of a chromosome 1 Replication of a chromosome occurs during Interphase When a chromosome replicates two chromatids are formed and the chromatids are held together by a centromere 2 A chromosome is made up of DNA Therefore replication of DNA is identical with