What percentage of hydrogen peroxide mostly stimulates the germination of a seed?

Pre-Ib Biology Lab By Zineb Ouazzani in collaboration with Elias Elghaldy and Sara Elabridi.

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Research question:What percentage of hydrogen peroxide mostly stimulates the germination of a seed? Purpose: The purpose of this lab is to define what percentage mostly stimulates the germination of a seed.The answer can be very useful.Farmers can use H2O2 to make their crops grow faster,which can provide seeds to grow faster,resulting in an economic increase in the agricultural section. Hypothesis: In my opinion, 8% of hydrogen peroxide will mostly stimulate the germination of the seeds.Statistics say that 3-10% range of amount of hydrogen peroxide will provide the seed with better resources ,thus germinating faster. Background Research: What is Hydrogen Peroxide? Hydrogen peroxide is a covalent compound made of two molecules of hydrogen and two molecules of oxygen,making it the simplest peroxide. It is a highly reactive peroxide, and may cause effects depending on the percentage use.Its chemical formula as shown below shows the decomposition of hydrogen peroxide when mixed with water or oxygen. 2H2O2 → 2 H2O + O2 The use of Hydrogen peroxide has emerged these last few years as the its use is proven to be efficient in several ways.Farmers have used hydrogen peroxide to stimulate crops growth and decrease the risk of fungal diseases.It is also used in city water and well water to keep the water clean (35% per 1000 gallons) and help stop diseases and in a way helpful in farms as it helps animals fight diseases( example of hogs without parasite eggs). Hydrogen peroxide is a growth promoter for all plants.It is a resistence drought factor and the seed is enhanced. What is photosynthesis?Photosynthesis is a process which plants,algaes or some bacterias go through which basically converts light energy into chemical energy. This process requires carbon dioxide and water,releasing oxygen as a byproduct. Photosynthesis begins when photosynthetic reaction centers absorbs light energy and stored into ATP by chorophylls.Some of the energy is used to remove electrons from water which

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are used to turn CO2 to organic compounds in a process called the Calvin Cycle.

Variable:Independent: Percentage of H2O2(4%,6%,8%,10% and 12%)Dependent variable: Germination of seedControl:Amount of H2O2(10ml),light,petri dishes,days,temperature,moisture,cotton, and humidity. Materials:

Material Amount Purpose

Seeds 150(Ten seeds for every trial). The seeds is one of the main factors of the experiment.In other words,where we will conduct the experiment.

Hydrogen peroxide 30 ml each of 2%,4%,6%,8%,10% and 12%.

Hydrogen Peroxide is the independent variable.

8.5 cm Petri dishes 15 The petri dishes is the “setting” of the experiment.

Coton 30( Two for each trial). A replacement of soil which also helps the seed.A seed won’t germinate with too much water,and coton absorbs hydrogen peroxide.

Graduated cylinder(10 ml) One or two depending on the groups need.

The graduated cylinder(s) is used to measure the amount of

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hydrogen perooxide.

Gloves 1 pair per person. Gloves is one of the safety precautions.Hydrogen Peroxide makes your hands dry,resulting in whiteness in your hands.

Distilled water 100 ml Distilled water is used to clean the materials once finished.

Tongs At least one pair. Tongs will help us measure hydrogen peroxide to the nearest percentage.

Procedure:Place all the materials in frontLabel the petri dishes. Place a circled piece of coton in every petri dish.Pour 5 ml of hydrogen peroxide in the petridish with the tongs.Place 10 seeds each in a petridish and cover it with another piece of coton.Pour 5ml of hydrogen peroxide over the coton.Close the petridish with its cover and place all the petridishes under light.Observe for 3 days and collect data. Data: Day 1:

Trial 1 Trial 2 Trial 3 Average

4% H2O2 110%

00%

110%

0.666.66%

6% H2O2 00%

220%

00%

0.666.66%

8% H2O2 330%

220%

110%

220%

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10% H2O2 110%

00%

110%

0.666.66%

12% H2O2 00%

110%

110%

0.666.66%

Bar Graph Day 1:

Day 1 Observation: The seeds that were soaked in 8% hydrogen peroxide showed the most results out of the other seeds. The other seeds showed different results,yet got the same average number.

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Day 2:

Trial 1 Trial 2 Trial 3 Average

4% H2O2 330%

220%

220%

2.33323%

6% H2O2 110%

330%

220%

220%

8% H2O2 660%

330%

330%

440%

10% H2O2 220%

330%

330%

2.66626%

12% H2O2 220%

110%

220%

1.66616%

Day 2 Observation: Seeds that have been watered with 8% hydrogen peroxide still show a better result than the other seeds with a success rate of forty percent. 10 percent H2O2 shown a better result than the other seeds with a range of ten percent. Seeds soaked in twelve percent are the seeds that least germinated.Day 2 Bar Graph:

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Day 3(Final Day):

Trial 1 Trial 2 Trial 3 Average

4% H2O2 4 40 %

330 %

330 %

3.333333 %

6% H2O2 330 %

550 %

440 %

440 %

8% H2O2 770 %

550 %

660 %

660 %

10% H2O2 330 %

330 %

550 %

3.636 %

12% H2O2 220 %

220 %

220 %

220 %

Day 3 Observation:

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Seeds that have been watered with 8% hydrogen peroxide have constantly shown the better result with a success rate of sixty percent.Suprisingly, seeds in the six percent hydrogen peroxide have shown better results in the last day than the ten percent,which in the previous day contained the second place.Twelve percent shows the least success, and four percent the second least. Bar Graph Day 3:

Average Bar Graph:

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Conclusion:Seeds that have been watered with 4% hydrogen peroxide showed little results .Seeds in Trial 1 have had a success of forty percent as the others had a success rate of thirty percentage.Most of the seeds barly germinated and the average is 3.33,thus a third of the seeds.Seeds in 6% hydrogen peroxide category have shown better results than the previous.The lowest rate is 30% and the highest is 50%.Seeds in this category have acheived a success rate of one half,which is pretty good.The average is 40% making it the second highest rate in this experiment.As the data table shows, seed that have been watered with 8% hydrogen peroxide have a higher percentage of germinating. More than half of the seeds germinated in each trial,resulting in an average of 6 seeds germinating out of ten.The percentage of a seed germinating under ten millimeters of 8% hydrogen peroxide is sixty percent.The results of 10% hydrogen peroxide showed less results than eight percent.Trial 3 is the only one to acheive a rate of 50%,as the others both have a rate of 30%,decreasing the average rate :3.6 seeds germinated out of 10.12%hydrogen peroxide has shown the least results with all the trials showing a success rate of 20%; ⅕ out of the total.The average rate is 20 %,the lowest average in this experiment,though the seed that germinated the most belonged to this group.Our hypothesis was correct.Seeds that were watered with eight percent hydrogen peroxide had the most success rate.

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Evaluation: In my opinion,our experiment is one of the most successful experiments in the classroom. We managed to bring all the materials which is a good start.We were well organized and didn’t fight once during the experiment. During the process,we measured hydrogen peroxide to the nearest millimeter to have precise data even if it took some time.Surprisingly,our group really put alot of effort in this science lab.Instead of putting the paper tissues in the petri dishes like the other groups, we cut 30 circles :2 pieces for each petri dish which shows that our work is not poorly done.Nevertheless,it took us a lot of time.We had several issues to deal with.The seeds weren’t available so we had to take seeds from the classroom.In addition, the timing of our experiment was shortened for some reasons which let us with less time to conduct our experiments,which affected our lab results. Sources of Human Error: There may have been sources of human errors.One of the errors may have been the amount of light that was projected towards the seeds which may have affected the steps of photosynthesis of the seed.In photosynthesis,the seeds absorbs Co2 and releases Oxygen as a byproduct.The oxygen couldn’t “flow” as it was trapped in the petri dishes,resulting in no CO2 at a moment and stopped the cycle.The temperature may have affected the germination of the seeds.These days, the temperature constantly changed day and night,maybe slowing the process.

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