Post on 18-Jan-2016
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Reproduction of CellsAsexual Vs Sexual Reproduction
Asexual ReproductionSingle parent passes complete copy of genetic information to its offspringIdentical to parent4 typesBinary fissionFragmentationBuddingParthenogenesis
Binary FissionDNA duplicates -> Cell grows -> Cell splits
FragmentationBody breaks into several pieces and grow new parts or whole organism
BuddingNew individuals split off from existing ones
ParthenogensisFemale makes viable egg that grows into an adult without being fertilized by male
Sexual ReproductionGenetic material given to offspring by two individualsOffspring are genetically different from parentsGametesReproductive cell (sperm or egg)Division of germ cellHaploid cells created through meiosisUnion produces zygote
MeiosisCell reduces chromosome number in new cells to half the number of the original cellSperm and egg (1n each, haploid)Combine result in zygote (2n, diploid)
MeiosisInterphaseBegins with duplicate set of chromosomes like mitosisTwo divisions results in four (1n, haploid) cellsMeiosis I and Meiosis II
Meiosis IProphaseChromosomes condenseSpindle fibers formHomologous chromosomes line up next to each other (synapsis)Tetrads align side by sideTwist around each other Portion breaks off to the adjacent chromatidCrossing over results in new mix of genetic information
Meiosis ISimilar to mitosisMetaphase IAnaphase IIndependent assortmentTelophase IResults in two cells with a chromosome from each pair of homologous chromosomes
Meiosis IIProphase II, no duplication of chromosomesMetaphase IIAnaphase IIChromatids separateTelophase IICytokinesis II4 new genetically different haploid cells
Genetic VariationCrossing overIndependent assortmentRandom fertilization
Development of GametesTestes in malesSpermatogenesis to create spermOvaries in femalesOogenesis to create ova1 egg and 3 polar bodies
Karyote