Non Vascular Plant
Non vascular plants are huge in the evolution of plants, because they begin the move of plants onto land. There are not a lot of characteristics that distinguish non vascular plants from other plants, but these characteristics did allow non- vascular plants to separate themselves from the previous group composed largely of algae. The four traits that we see begin to develop are apical meristems, walled spores, gametangia, and one of the most common called alternation of generation. Many of these traits are used additionally in the life cycle of no vascular plants as well. Apical meristems begin to show evidence of roots, and briefly give insight into the upcoming evolution of vascular plants. Gametangia, revolves around the idea that the sperm and eggs of new developing plants with be within some type of embryo rather than free swimming within the water. This was exteremly important to reproduction, as plants begin to move onto land. The third trait, spores within the walls is also important to the move onto land, because it allows for better protection in the structure of plants, and allows them to begin to keep nutrients that they have gathered or absorbed. The final trait, alternation of generations is crucial in the lifecycle, because it describes the idea that first you start with a haploid gametophyte cycle, which then transitions into a diploid sporophyte life cycle.
This brings us to our life cycle of non-vascular plants. Non vascular plants begin as haploid gametophytes, and since it is haploid this is produced by the process of mitosis. The next step is the process of fertilization. The process of fertilization helps in the process of becoming a diploid sporophyte, which then allows us to move into meiosis, and soon after starting the process again. The spores in the first step of meiosis will go through the process with the female part, archegonia, or the male part antheridia. However, both parts are needed, because then the spores fertilize the egg to start fertilization. Successful reproduction in these plants is very important, because of their importance to humans.
In the non-vascular group of plants you will see everything from mosses, hornworts, and liverworts. While the uses of non-vascular plants are not as important as the use of vascular of seed plants they play a big role in our environments. Because these plants are so close to the ground and reproduce quicker than other plants they have the ability to continue to keep important nutrients in the soil, such as carbon and nitrogen. In addition on common moss many people know about is peat moss, which we are constantly finding new uses for, but the main use to date is fuel, and energy. The next evolutionary step taken is to the step of vascular plants.
The idea of vascular plants is huge to the development of plants. The main traits that we will see in addition to vascular tissue also evolve in part due to the evolution of vascular...