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