1. The Effects of Caffeine on Plant Germination
By: Erin Chandler

2. Question
How will different amounts of caffeine exposure effect the growth and germination of radish seeds?

3. Background Information
#1 drug in America
Caffeine is better known as trimethylxanthine
The chemical formula of trimethylxanthine is C8H10N4O2
Naturally made in some plants
Used in sports
Caffeine and the brain
Growth hormone or inhibitor?
Raphannus Sativus
Growing conditions
Process of germination

4. Hypothesis
If seeds are exposed to caffeine solutions of various concentrations, then those exposed to the highest concentration will have higher germination rates and longer root lengths then those exposed to solutions with lower caffeine concentration.

5. Materials bleach dropper distilled water gloves 5 beakers
200mg caffeine pill
mortar and pestle
radish seeds
20 Petri dishes
12 pieces of filter paper

6. Procedure
Wear gloves as seeds were soaked in a bleach/water solution and rinse
Label beakers 1-5 and fill beaker 1 with 100 mL of water
Crush caffeine pill and put it in beaker 2 with 100 mL of water, stir
Take 10 mL from beaker 2 and add to beaker 3 along with 90 mL of water, stir
Take 10 mL from beaker 3 and add it to beaker 4 along with 90 mL of water, stir
Take 10 mL from beaker 4 and add it to beaker 5 along with 90 mL of water, stir
Label Petri dishes according to caffeine concentration and then trials 1-4
Soak filter paper in 3 mL of solution and place in appropriate Petri dish
Put 10 radish seeds in each Petri dish
Put Petri dishes in a dark enclosed area for a certain amount of time

7. Variables Control: seeds exposed to distilled water
Independent Variable: amount of caffeine in each solution
Dependent Variables: amount of seeds that germinate, and root lengths
Constants: amount of solution on filter paper, temperature, number of seeds in each Petri dish, temperature of water

8. Data
Seeds Germinated

9. Data (2)

10. Discussion
The data in this experiment showed that, the caffeine did cause a change in the way the seeds germinated and grew
The solution with the most caffeine had the least amount of seeds germinated and in the control the most amount of seeds germinated
The t test showed that all data can be interpreted because all results are lower then .05, the conclusion that can be drawn according to the t test is that caffeine has a major effect on the plant’s germination
The hypothesis was not supported by the results generated in this experiment
These results show how caffeine has a negative effect on the seeds, and that stimulants do not help the growth of plants
Caffeine is the number one drug used in America, it can be concluded that caffeine most likely does not have a positive effect on the millions of people that consume it every day

11. Changes and Further Experimentation
If this experiment were to be conducted again, more trials would have been very beneficial
It also would have helped to put the Petri dishes in plastic bags so that the seeds did not dry out. This would have allowed for more growing time for the seeds which would result in more data and more accurate results. Also, testing even more amounts of caffeine on the seeds may have shown more significant results so that better conclusions could have been drawn
If a person wanted to take this experiment further they could have experimented with different kinds of seeds, put the seeds in different environments or tested the seeds with other drugs similar to caffeine

12. Thank You
Brian, M., & Bryant, C. W. (n.d.). How Caffeine Works. Retrieved October 6, 2010, from Discovery Health website:
     wellness/drugs-alcohol/caffeine1.html
Caffeine. (n.d.). Retrieved January 30, 2011, from chemBlink website:
     
Enblogopedia. (n.d.). What are the effects of caffeine? Retrieved September 5, 2010, from Enblogopedia website:
     the-effect-of-caffeine-on-plant-growth/
Greenaway, T. (2001). Plant Life. Austin, TX: Raintree Steck-Vaughn Publishers.Growing radish from seed. (2000). Retrieved September 5, 2010, from GardenAction  website:
     fruit_veg_mini_project_june_1b_radish.asp
Olympic Gold? A New Effect of Caffeine Boosts Performance. (2010, June 30). Science Daily. Retrieved from
     06/ htm
Reid, T. (n.d.). Caffeine-What's the Buzz? National Geographic. Retrieved from