PHIL 1021 Chapter : Img23 2
Document Summary
Asexual reproduction is rare in vertebrate species, but is possible: http://news. bbc. co. uk/earth/hi/earth_news/newsid_9139000/9139971. stm: many plant species can reproduce both sexually and asexually. Some methods of asexual reproduction: fragmentation can be an artificial process (cuttings) or a natural process, sometimes a parent plant sends out horizontal stems/runners that can lead to completely new plants, reproductive leaves (kalanchoe sp. Thousand mother plant: asexual reproduction is natural cloning where all the offspring are genetically identical to the parent plant. Sexual offspring combine the genes from two parents and are genetically different from their parents. Advantages to sexual reproduction: beneficial in changing environments. Genetic variation produces new traits in offspring: reduces parasitism. Host defenses change: dna repair during crossing over. Angiosperm life cycle (fig 44. 1) alternation of generations revisited (know in detail!!) 2 distinct multicellular adult forms: sporophyte: diploid plant which produces haploid spores, gametophyte: haploid plant which produces gametes. In non vascular plants the gametophyte was dominant and sporophyte was dependent.
