A student investigated the effect of radiation on the germination of bean seeds. He thought that exposure to radiation would limit the seeds ability to germinate (grow) much like ultra-violet light causing skin cancer. Three hundred seeds were soaked in water for one hour. They were then divided into three groups of 100 beans each. One group was placed in a microwave*oven on high for three seconds. Another group was microwaved on high for six seconds. The last group was not microwaved. The seeds were then planted in three separate flats and given the same amount of water. The flats were placed in a location with a constant temperature of approximately 27 degrees Celsius. Each day for two weeks the number of seeds that germinated each group was recorded. The results of his experiment are noted below:
Length of exposure
3 seconds of radiation
6 seconds of radiation
No radiation
# Germinating seeds
54 seeds
26 seeds
88 seeds
*Note: microwaving the seeds exposes them to radiation Complete each of the following:
Identify the student's hypothesis: If seeds are exposed to radiation then seed germination will be decreased.
Identify the independent variable: amount of radiation
Identify the dependent variable: seed growth or germination
Identify the other variables the student needs to consider/control during this experiment: soil (type, amount), fertilizer (concentration, type), amount of sunlight, temperature, presence of pests, type of bean, age of seeds, temperature of water (soaked, and applied), time of planting, range of experiment, how much water
Identify the control group in this experiment: beans without radiation
Identify the experimental group: two groups of seeds exposed to radiation
What conclusions might the student draw from this data? More seeds germinate when not exposed to radiation; increased radiation yields a decrease in germination - hypothesis was supported
What recommendations might you suggest for further study or for improvement? try more radiation, different species of beans or even different seeds
A student investigated the effect of radiation on the germination of bean seeds. He thought that exposure to radiation would limit the seeds ability to germinate (grow) much like ultra-violet light causing skin cancer. Three hundred seeds were soaked in water for one hour. They were then divided into three groups of 100 beans each. One group was placed in a microwave* oven on high for three seconds. Another group was microwaved on high for six seconds. The last group was not microwaved. The seeds were then planted in three separate flats and given the same amount of water. The flats were placed in a location with a constant temperature of approximately 27 degrees Celsius. Each day for two weeks the number of seeds that germinated each group was recorded. The results of his experiment are noted below:
Complete each of the following: