1.Earthworm reaction to chemical stimulus of ammoniaGroup 5:Kenia CarrilloAmandeep GillNavdeep Hans

2. Objective/s of the experiment: Initial objective: To find out whether or not earthworms sense odor orsmell. How we tested it: Observing the earthworms reaction to ammonia.After experiment: Objective #2: find out how earthworms use theirsense of smell Objective #3: find out how ammonia affectearthworms 3. Our prediction: Since reaction to odor was being measured, we predicted that earthworms would resist the side with ammonia and go on the side that contained the paper towel soaked with water, since water does not have an odor. 4. Materials & methodsMaterials: Paper towels Ammonia Water Six earthworms 2 beakers (100 ml) Three lab trays 5. Procedure: The first step for the experiment was to soak thepaper towels. One of the paper towels was saturated in tapwater (the control group) and the other inammonia. Next, each of the damp paper towels were placedon the lab tray side by side. Between the paper towels, in the center of thetray, a small space was left dry (no water orammonia) to encourage the earthworms to moveto the wetter environments. Three earthworms were set in the center and leftfor 10 minutes. 6. Set up:ammoniawaterEarthworms on dry paper towel 7. Procedure continued Three different trials were done for thisexperiment for consistency and accuracy. The first two trials each had three differentearthworms, but since there was not enoughworms for the third trial two worms from trial 2and one from trial 1 was used in the final trial. Lastly, the were collected and analyzed. 8. Results & Data 9. Results & Data 10. Trial #1 11. Trial #2waterThirdworm(underpapertowel)AmmoniaAll three worms went to the side with water. 12. Trial #3Worm water2 ammonia(underneathpapertowel) Worm 3 (Dead) Worm 1 13. Conclusion: Earthworms lack lungs and noses, and they donot smell or taste in the same way thatmammals do. They are, however, able to pick up and respond to chemical signals in the air through the use of chemoreceptors, which enables it to detect chemical stimuli with its entire body. Earthworms dont respond well to the chemical stimulus of ammonia; direct contact with ammonia can cause death. 14. References: Brooks, L., 2011. Can earthworms detect smell? eHow http://www.ehow.com/facts_6904094_can earthworms-detect-smell_.html. (11 November 2011). Farabee, M.J., 2010. The excretory system. Maricopa.http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookexcret.html. (11 November 2011) Hickman, C.P., Roberts, L.S., Keen, S.L., Eisenhour, D.J.,Larson, A., and IAnson, H., 2011,Integrated Principals ofZoology, Mcgraw Hill, New York City, 376 p. 15. Video (Trail #3)