Wild About Radishes PCA Student Responses for Item 7: Describing Sources of Error
Student Response 1
One possible source of error: One error she could have made was putting them in an area where some
of the plants got more sunlight then others. This would effect the investigation results because plants neede
light ot grow and if one plant received more sunlight then another then that one would grow better.
Another possible source of error: Another error she could have done could be that she packed the soil
down more in some of the pots making hard for the water to get to the seed. If water can’t get to the soil
then the plant won’t grow as well as it could.
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Student Response 2
One possible source of error: Amanda did not repeat the trials. Not repeating the trials would not give
her an accurate measurement on the plants growth. She could have made a mistake the first time.
Another possible source of error: Measuring the tallest radish leaf could be another error because
a radish plant could just have shorter leaves or not as many leaves as other plants.
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Student Response 3
One possible source of error: Light might be one possible source of error because most plants need
light to grow.
Another possible source of error: Since Amanda was measuring the tallest leaf of each plant then it might
be an error because she could measure each plant itself to get a better test results.
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Published by the Science Assessment Team of the Washington Office of the Superintendent of Public Instruction on September 27, 2007.
Copyright © 2007 by Washington Office of the Superintendent of Public Instruction (OSPI)
All rights reserved. Educational institutions within the State of Washington have permission to reproduce this document. All other individuals wishing to
reproduce this document must contact OSPI
OSPI Science Assessment
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September 14, 2007
Wild About Radishes PCA Student Responses for Item 7: Describing Sources of Error
Student Response 4
One possible source of error: One possible source of error in Amanda’s investigation was that she didn’t
repeat the entire investigation. This could have affected the results because she could have had bad data the
first time and without repeat it she wouldn’t know if it was bad.
Another possible source of error: Another possible source of error could have been how much sunlight each
plant recieved. This could affect it because if one plant recieved more sunlight it could grow larger than the.
other plants and ruin the results
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Student Response 5
One possible source of error: One possible source of error is that one of the plants had to much light or had
more light than the others. It could affect the investigation because light also helps plants grow so if 1 plant
had more light than the others it would grow faster.
Another possible source of error: Another possible source of error is if one of the plants didn’t have as
much light as the others then it wouldn’t grow as fast. And it would affect the investigation by not having a
fair trial and finding the wrong results.
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Student Response 6
One possible source of error: One possible source of error in Amanda’s investigation was having different
acidity water put on each plant it it was just one kind of acidity water The plant would have grown the same
hight and make the results more accurate for this results
Another possible source of error: And having to put different amount of water with the plants would have
been better because if she puted different amount of water in the pot every week, it would shown her how
acidity water effect plant growth
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September 14, 2007
Wild About Radishes PCA Student Responses for Item 7: Describing Sources of Error
Student Response 7
One possible source of error: Amanda watered the radish plants every three days. That could of affected the
growth of the radish plants by not getting enough water.
Another possible source of error: Amanda recorded the height of each radish plant after watering it, which
she watered every three days. The plant might have grown but, by that time got smaller because it was dying.
So how can her recording be accurate.
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Student Response 8
One possible source of error: is the amount of soil she could put to much soil in one and it could store
more water
Another possible source of error: amount of sun light one could get to little and not grow as much
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Student Response 9
One possible source of error: One possible error Amanda could of done to help the plants from dieing was
to give the radish plants more sun light to use the light for photosynthesis.
Another possible source of error: Another possible error Amand could of done to help the plants from
dieing was to give the radish plants more water to help oxygentate the root so it can grow.
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Student Response 10
One possible source of error: One possible source of error in Amanda’s investigation was not using any
water with a pH higher than 7 or lower than 4. PHs higher than 7 and lower than 4 could have different.
effects on the plants height.
Another possible source of error: An other possible source of error in Amanda’s investigation was the
amount of soil and size of the pots she used. Depending upon the amount of soil, different amounts of
nutrients might have been available. The size of the pot could have limited root growth and affected.
plant height
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September 14, 2007