acteria grow so easily and so numerous. Some species reproduce both asexually and sexually depending on which one the conditions are more suitable for. (Encarta, 1)Organisms that reproduce asexually are particularly well suited for establishing entire populations. This is the case for many weeds and pests. The offspring of organisms that reproduce asexually are identical to their parents and to each other. That means they cannot mix genes, and therefore dont adapt or evolve as quick as other organisms do. (Encarta, 1).Sexual Reproduction is the primary means of reproduction for most multicellular animals and plants. For higher invertebrates and all vertebrates, except the few that reproduce by Parthenogenesis, sexual reproduction is the way they must reproduce. Sexual reproduction is essentially cellular in nature, meaning that it involves the fertilization of one sex cell by another, producing a newly fertilized cell called a zygote, which then develops into a new organism. In some lower forms, the union of two isogametes (gametes that are the same structurally but not physiologically) occurs, and is called isogamy or conjuction. The fusion of two clearly different kind of gametes is called heterogamy.(Encarta 4)Sexual reproduction is very significant, in that because of the fusion of two entirely different nuclei, the offspring could inherit an endless varied combination of characteristics, which may help improve the species. This is why organisms which reproduce sexually adapt quicker than do asexually reproducers. Multicellular plants alternate sexually and asexually reproducing generations. First, the plant starts as a gametophyte, which produces gametes. Then, it undergoes fertilization, and then mitosis, forming a sporophyte, which produces spores. When the sporophyte is ready to reproduce, it undergoes meiosis and produces spores. These form a gametophyte, and the cycle starts again and again until the plant dies.Pollinatio...
