Organism Module Lab Assignment - Answer Key Total: 35 marks (worth 5% of final grade) Part 1: Experiment Outline 1. Plant Classification (a) How are these plants classified? Fill in the information for the following plants (entering the common name into Wikipedia works well). Be careful with your spelling. Then, on a scale of 1-5 (1 is least likely; 5 is most likely), indicate whether you think the plant might be a suitable host (food source) for the tobacco hornworm, based on this information. There are no marks for your "Host?" answers but you'll need to explain your rationale for the next question. (1 mark) Class/ Clade Asterids Solanales Solanaceae Order Family Genus Nicotiana Asterids Solanales Solanaceae Nicotiana Asterids Solanales Solanaceae Nicotiana Asterids Solanales Solanaceae Solanum Asterids Solanales Solanaceae Capsicum Asterids Asterales Asteraceae Asterids Gentianales Apocynaceae Callistephus Asclepias Species Nicotiana alata jasmine tobacco 1 Nicotiana benthamiana benthamiana 1 Nicotiana rustica Aztec tobacco 1 Solanum lycopersicum tomato 2 Capsicum annuum cayenne pepper 3 Callistephus chinensis Asclepias syriaca milkweed 5 Common Name Host? China aster 4 (b) Briefly explain the rationale for your answers in the "Host?" column; i.e. based on relatedness, why did you think each plant would or would not be a suitable host for the tobacco hornworm? (2 marks) Species in the Solanales 2. Defense Compounds (a) Given the following information about key chemical defense compounds, assess again (using the same scale of 1-5) whether you think the plant might be a suitable host for the tobacco hornworm. Again, there are no marks for these answers, but you'll need to explain your rationale for the next question. Plant jasmine tobacco nicotine (alkaloid) Key Leaf Defense Compound Compound in Leaves? low/absent Bethamiana nicotine (alkaloid) Aztec tobacco tomato nicotine (alkaloid) solanine (alkaloid) cayenne pepper solanine (alkaloid) China aster eudesmane (sesquiterpenoid) milkweed cardenolide (steroid) present present present present present present Host?
(b) Given this new information, briefly explain why your answers in the "Host?" column changed or stayed the same. (1 mark) Provide the following information about your class (lab section's) herbivory experiment: 1 mark: questions #3-7; no marks: questions #8-9; 2 marks: question #10 3. Research question: Do hornworms have a preference between nicotine producing plants (Aztec tobacco) and a non-nicotine producing plant(tomato)? 4. Hypothesis and prediction(s): H: The hornworms will weigh more after 5 days when feeding on Aztec tobacco (nicotine) than when feeding on tomato (solanine). P: If hornworms are fed with Aztec tobacco plants, then they will weigh more after 5 days than hornworms fed with tomato plants. 5. Independent variable and the different experimental/control groups: IV: Plant Species CG: Tobacco plants (11) and Tomatoes (10) 6. Dependent variable(s) and the observations you will make: DV: Mass of hornworm (g) Observations: 7. Number of biological replicates in each experimental/control group: BR: Hornworms (24) CG: 8. Which bench groups are responsible for which components of the experiment: Refer to Google Doc 9. Which open lab observation(s) your bench group is/are responsible for. 10. List 2 confounding variables that could