Plant Adaptation Essay

As plants evolved, moving from the sea to land, there were many adaptations that needed to occur to sustain the new mode of life. Adaptations addressed the major problems of how to prevent water loss, how to transport water, and how to reproduce in a newly dry environment (Lecture 4). Different organisms addressed these issues in a variety of ways, giving rise to anatomical differences in tissues and biochemical changes, which contributed to the rise in genetic variation of plant species. First, plants had to use adaptations to prevent water loss in the new, dry environment. The first plants to evolve to deal with this were the bryophytes, or non-vascular, plants. These plants had a cuticle, a waxy covering of leaves which helps to trap

While maintaining all vascular structures, gymnosperms and angiosperms adapted to reproduce in different ways, while both are plants with seeds. Both also contain microspores and megaspores, the male and female gametes of the plants, respectively. Gymnosperms produce naked seeds, or plants that are not enclosed in the ovary for protection. The gymnosperms also developed tracheids, to aid in water transport. There are four living phyla which are classified as gymnosperms, including ginko, cycad, conifer, and gnetophyte (Lecture 5). The next group, angiosperms, contribute many previously unseen adaptations. First, these plants have a different mode of reproduction with an enclosed seed, protected in the ovary. This group holds the unique characteristics of fruits and flowers, which are evolutionarily beneficial because these structures attract pollinators, to spread pollen, and result in a farther reaching spread of genetic material for the angiosperms (Lab 2). The xylem of the plant also has vessels and tracheids, a new adaptation that most gymnosperms lack (Lecture 7). The angiosperms can be further divided into monocots and eudicots, which have a number of differences including number of cotyledons and leaf vein organization (University of California, Berkeley). The last trait that angiosperms developed to be better suited for life on land is double fertilization, where there is a time that the endosperm contains three sets of chromosomes, and is not in diploid