Students should be able to:
It is possible that the group of organisms that are referred to as plants today, may have had a few lines of evolutionary origin. Non-vascular plants, such as mosses and liverworts, that have remained “amphibious” probably evolved along a separate line from the larger, vascular, terrestrial groups that dominate the earth’s landscapes today. However, all plants may have evolved from plant-like protists, more specifically, the algae. There is evidence for this view, which is reviewed elsewhere. Both algae and plants share certain key characteristics, and both are eukaryotic, i.e., have membrane–bounded specialized cell compartments (organelles) in which various metabolic functions take place.
The early plants that colonized the terrestrial environment must have tackled formidable challenges in temperature and moisture fluctuations, the force of gravity, etc. Some of these (e.g., mosses and liverworts referred to above), have remained restricted to moist environments, and have not really evolved the structures that are vital for terrestrial challenges.
Plants are primarily terrestrial, multicellular eukaryotes that have well developed tissues, even though some of them lack vascular tissues for conducting water and organic materials. Plants have chlorophylls and other pigments that enable them to manufacture organic compounds in the process of photosynthesis. Their cells contain cell walls that are made of cellulose. Recall that the cell wall materials in bacteria and fungi are made of peptidoglycan and chitin, respectively.
Plants are broadly divided into vascular and non-vascular, and the latter into seedless vascular, and seed vascular plants. The seed plants, in turn, are divided into gymnosperms (non-flowering plants) and angiosperms or, flowering plants. Flowering plants may be either monocotyledonous or dicotyledonous, depending on whether they have single or paired seed leaves. Numerous other morphological and anatomical characteristics reflect these categories and sub-categories of plants.
In both terrestrial and aquatic environments, plants provide invaluable support to the ecosystems through primary production (synthesis of foods) and production of oxygen and shelter to countless animals. Plants provide us medicines, building materials in the form of wood, fibers for fabric and bags, and numerous other products. Thus, it is simply inconceivable to imagine life on earth without the vital roles played by plants
Pre-Lab Activity #1 - Life Cycles
Using resources available to you, find representative labeled imagery of the following:
Pre-Lab Activity #2 - Imagery of typical nonvascular and vascular plants.
Using resources available to you, find representative labeled (if possible) imagery of the following:
Pre-Lab Activity #3 - Plant Dissection
Dissection guide for a typical flowering plant.
Pre-Lab Activity #4- Data Collection Sheet
Download and print out the Data Collection Sheet forPlant Diversity
The Laboratory Activities and Data Collection
Lab Activity #1 - Mosses
Lab Activity #2 - Liverworts (Marchantia sp.)
Lab Activity #3 - Seedless Vascular Plants
Lab Activity #4 - Ferns
Lab Activity #5 - Gymnosperms
Lab Activity #6 - Angiosperms (Flowering plants)
Post-lab Activity and Data Analysis
Results and Analysis