biology reproduction

Biology : reproductionasexualMitosoisONE parentordinary celldivide into twogenetically identical cellssame genes as parentsclonesno variation in off springprocessx shaped chromosome2 identical halvessplits down middletwo identical half chromosomestwo sets of DNA strandsmembrane forms round eachDNA replicates itselfreplacement cellsplant growthanimal growthorganisms producing offspringbacteriasome plantssexual reproductionMeiosisTWO parentsproduce gameteseggsspermhumanscontain 23 chromosomeshalf number chromosomes in normal cellone of each chromosome instead of twofertilisationegg & sperm fusesperm (gamete) + egg (gamete) = fertilised egg (zygote)full number of chromosomesinherit featuresboth parentsmixture of chromosomesgenetic variationgenetically different offspringplant cloningasexual reproductioncuttingsfrom good parent plantsquick & cheaptissue culturefew cellsgrowth mediumhormonesclonesadvantagesmany plantsquicklynot much spacegrow all yearREDUCED GENE POOLanimal cloningembryo transplantartifically fertilisesperm cellegg cellsplit embryo before specialisationcloneimplantclone embryos into other cowsbaby calves all genetically identicaladvantages100s of ideal off spring every yeardisadvantagereduced gene poolfewer allelesclosly relatednew disease can kill allno resistance from alleleAdult cell cloningDolly the sheepuses complete set of body cell chromosomes into a denuclearated egg celltissue culturestem cellstreating diseasehumantreat diseases form stem cellsreplacement organsnot rejected by immune systemunethical?fusion cloningadult cell - fused - embryonic stem cellproperties of stem cellgenes of adult cell
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