REPRODUCTION OF PLANTS Plants, like animals, undergo meiosis and fertilization. There is halving of the number of chromosomes in the sex cells, leading to gametes. The male and female gametes will fuse in fertilization in order to create a diploid cell with the full number of chromosomes. Of course, this is not the exact process happening in plants as happens in animals. There are two separate generations of organism. The first is the gametophyte generation that begins with a spore that is haploid. The spore will divide by mitosis to make many identical haploid spores. Ultimately, sexual reproduction takes place, leading to a sporophyte generation, starting with a zygote. These develop and then some of the cells form spores again, restarting the gametophyte generation again. The main difference is that haploid cells will undergo mitosis as well as diploid cells. Figure 43 shows the life cycle of the plant:
While plants do some things different among the different types of plants, we’ll take a look at the life cycle of the angiosperm plant, which are the flowering plants. Most of these are land plants and none will have locomotion. The gametes are delicate single cells with the need for a mechanism for two gametes to reach each other in a safe manner. There must also be a way for the dissemination of offspring so that there isn’t competition between the different organisms for light, soil, and water.
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