Purpose: To see the effect of an acid introduced during seed germination, on the length of the plant roots. Also shows how salt can affect the seed germination. Acid can be introduced to seeds during germination if there is acid rain. Knowing the results of acid rain on seed germination will help us understand how to grow pants better, and how to have more successful germination. Salt can be introduced into a seed during germination because salt is put on roads and the salt builds up and can contaminate the soil. Knowing the effects of salt on seed germination will allow us to know for sure if the salt is affecting the plants growth or not.
Hypothesis: If acid is introduced to the seed during germination, then the roots will not grow as long as the seeds that are given water.
Materials: Refer to lab handout
Procedure:
Part A 1. Fold a paper towel until it fits into a petri dish 2. Put the folded paper towel into the petri dish 3. Pour 12ml of water into the petri dish (inside the paper towel) so that the paper towel absorbs the liquid 4. Place 10 seeds(peas, beans or corn) into the petri dish (inside the paper towel) 5. Seal lid on petri dish with tape 6. Pour 12 ml of pH3 acid into a graduated cylinder 7. Repeat steps 1-5 with the pH3 acid instead of water 8. Pour 1.5ml of ph3 acid into a graduated cylinder 9. Mix 13.5 ml of water with the 1.5ml of pH3 acid to create pH4 acid 10. Repeat steps 1-5 with 12ml of the ph4 acid 11. From the extra ph4 acid, pour 1.5 ml of the pH4 acid into a graduated cylinder 12. Mix 13.5 ml of water with the 1.5ml of pH4 acid to create pH5 acid 13. Repeat steps 1-5 with 12ml of the new pH5 acid
Part B 1. Wait 1 week for the seeds to have time to germinate/grow 2. Remove lid from the petri dishes (all four) 3. Measure the root length on the seeds exposed to pH3 acid 4. Record the results in a table 5. Repeat steps 1-4
References: "Science Project." Science Project. N.p., n.d. Web. 29 Oct. 2012. <http://www.selah.k12.wa.us/soar/sciproj99/CodySciProj.html>. Rayle, David L., and Robert E. Cleland. "The Acid Growth Theory of Auxin-induced Cell Elongation Is Alive and Well1." Plantphysiol.org. N.p., 1 Apr. 1992. Web. 29 Oct. 2012. <http://www.plantphysiol.org/content/99/4/1271.full.pdf>. "Plant Hormones and Growth Regulators." BIOSYNTH : Plant Growth Regulators. N.p., n.d. Web. 29 Oct. 2012. <http://www.biosynth.com/index.asp?topic_id=139>.