Question

A student hypothesized that lettuce seeds would not germinate (begin to grow) unless they were covered with soil. The student planted 10 lettuce seeds under a layer of soil and scattered 10 lettuce seeds on top of the soil. The data collected are shown in the table below.To improve the reliability of these results, the student shouldA) conclude that darkness is necessary for lettuce seed germination B) conclude that light is necessary for lettuce seed germinationC) revise the hypothesisD) repeat the experiment using a larger sample size

Answer 1

To improve the reliability of the lettuce seed germination experiment, the student should repeat the experiment with a larger sample size and ensure consistent conditions. Investigating the role of the phytochrome system and light exposure in germination may also provide insight.

Step-by-step explanation:

To improve the reliability of results from an experiment to determine whether lettuce seeds require darkness for germination, the student should consider repeating the experiment but with improvements. One option is to use a larger sample size to reduce the impact of random chance on the outcome and increase the confidence in the results. Another approach could be to ensure that the conditions such as water availability, temperature, and soil type are consistent for both sets of seeds to isolate the variable of light exposure more effectively.

Additionally, the student could explore the role of the phytochrome system as some seeds, like lettuce, are known to require light for germination. In such cases, exposure to light converts the inactive form of phytochrome (Pr) to its active form (Pfr), signaling the seed to germinate.

Answer 2

Final Answer:

To improve the reliability of these results, the student should C) revise the hypothesis.

Step-by-step explanation:

The student's initial hypothesis was focused on the necessity of soil covering for lettuce seed germination. However, the data collected may suggest a different factor influencing germination. The student observed seeds both covered with soil and scattered on top of the soil, implying that light conditions might be a variable affecting germination.

By revising the hypothesis to consider the role of light in lettuce seed germination, the student aligns the hypothesis with the experimental setup. This adjustment allows for a more accurate understanding of the factors influencing the results. It is crucial to base conclusions on observed data and adapt hypotheses accordingly.

Thus the correct option is C