PLANT MORPHOLOGY STATIONS ACTIVITY KEY A: Stem Section 1. Name the structure labeled #5. Stoma (stomata) 2. What is the “local name” for the ground tissue system marked #7? Cortex if lateral to the vascular bundles, pith if medial to them. 3. Name the red and maroon cells (#15, 17). Hint: when mature, these cells are dead. Xylem cells B: Schefflera (Umbrella plant) 4. What kind of leaves does this Schefflera plant have? Compound. Five leaflets attached to one petiole. No axillary buds next to leaflets. 5. Is Schefflera a monocot or a dicot? Belongs to dicot class, as its leaf veins are netted, not parallel. For a short video on monocots vs. dicots, go to http://www.diffen.com/difference/Dicot_vs_Monocot C: Root section 6. What is/are the color(s) of the stele on this model? Green and orange 7. Identify the mitotic figure at which the piece of tape is pointing. Anaphase 8. Identify the tissue containing the mitotic figure. Root tip or apical meristem!! D: Plant cell 9. In what plant organ(s) would a plant cell like this one be found? Why? The plant cell model has chloroplasts, so a cell like this might be found in a leaf or in a stem that does photosynthesis. E: Leaf section 10. Which epidermis is the top (sun-facing) layer in this model? How do you know? The epidermis WITHOUT stomata is the top-facing layer. Most plants’ stomata are located on the underside of the leaves. 11. What is colored in red? (Be specific.) Xylem. 12. What organelles are visible inside the guard cells? Chloroplasts. (Note that the epidermal cells lack chloroplasts, which makes sense – the sun has to pass through the epidermis unimpeded. F: Partially decomposed leaf (please handle with care!) 13. What tissue system is still visible in this partly decomposed leaf? Its vascular tissue system. 14. Look up the word “lignin” in the marked passage of the biology book, and explain how it relates to the previous question. Lignin is a macromolecule deposited in secondary cell walls. Xylem cells develop secondary cell walls to strengthen them in their role of conducting water up the tree. (It also leads to their death, which makes creates tubes perfect for moving water.) G: Twig 15. How many years’ growth can be identified on this twig? 4 years’ growth Hint: look for the scar left when scales that protect the terminal bud in winter fall off. This scar completely encircles the twig. H: The Veggie Challenge! 16. Sort the vegetables at this station into the “root,” “stem,” “leaf” or “other” categories. ROOT Beet STEM Celery Potato (tuber) Ginger (rhizome) LEAF Onion bulb* OTHER Cauliflower (terminal bud) Brussels sprouts (axillary buds) *Bulb, in botany, is a structure that is the resting stage of certain plants, particularly perennial monocots. It consists of a relatively large, usually globe-shaped, underground bud with overlapping leaves (food reserves) arising from a short stem. The food reserves enable the plant to lie dormant when water is unavailable (during winter or drought) and resume its active growth when favorable conditions prevail. So the onion bulb could have also been placed in the STEM category.