Plastids — Diversity, Shape & Function
Description
This interactive virtual lab takes students through the full process of studying plastid diversity, from collecting live plant and algal samples at simulated real-world sites, such as pond water for Spirogyra and Zygnema, an aquarium for Elodea, freshwater rocks for Cladophora, and a garden or kitchen for tomato, carrot, and potato, to preparing wet-mount slides and observing them under a virtual microscope at increasing magnifications. Students sort plastid types by their traits, match chloroplast shapes to the organisms that possess them, and apply iodine staining to reveal starch grains in leucoplasts, with each observation automatically compiled into a field and lab notebook summarizing source, plastid type, shape, and staining result.
Learning Outcomes
By completing this lab, students will be able to distinguish chloroplasts, chromoplasts, and leucoplasts by their pigmentation, membrane structure, and function within plant and algal cells. They will be able to identify and describe the four chloroplast shapes covered, spiral, stellate, discoid, and reticulate, and correctly match each shape to its source organism (Spirogyra, Zygnema, Elodea, and Cladophora). Students will be able to demonstrate proper wet-mount slide preparation and microscope technique, including selecting appropriate magnification and focusing to resolve fine organelle structure. They will also be able to explain the biological basis for chromoplast pigment accumulation during fruit ripening and for starch storage in leucoplasts, including the role of iodine staining in visualizing starch grains under the microscope.