Nature of Science Review

Front

What should a scientist do if a hypothesis is NOT supported by data?

Back

Carry out further investigations.

Answer explanation

If a hypothesis is not supported by data, the scientist should carry out further investigations to gather more evidence. This approach allows for a deeper understanding and potential refinement of the hypothesis.

Front

The bar graph shows the population of bacteria at different temperature ranges. What can be concluded about the bacteria from the data in this graph?

Back

They prefer temperatures between 20°C and 30°C.

Answer explanation

The graph indicates that the bacteria population is highest between 20°C and 30°C, suggesting they thrive in this temperature range. This supports the conclusion that they prefer temperatures between 20°C and 30°C.

Front

What is the responding variable (dependent variable) in an experiment testing the hypothesis: “Drinking too many soft drinks causes a loss of calcium in the bones of teenagers”?

Back

the level of calcium in the teens

Answer explanation

The dependent variable is what is measured in the experiment. In this case, the hypothesis states that drinking soft drinks affects calcium levels, making 'the level of calcium in the teens' the correct responding variable.

Front

Helen is studying the growth of two different types of plants. She planted two of each type of plant in locations with different levels of sunlight: full sun, partial shade, and full shade. For five weeks, Helen records the number of new leaves on each plant. Which of the following statements correctly describes the independent and dependent variables in Helen's experiment?

Back

The independent variable is the amount of sunlight, and the dependent variable is the number of new leaves

Answer explanation

In Helen's experiment, the amount of sunlight is manipulated to observe its effect on plant growth, making it the independent variable. The number of new leaves is measured as the outcome, thus it is the dependent variable.

Front

What is the main reason for repeating an experiment multiple times?

Back

To ensure the results are consistent and reliable.

Answer explanation

Repeating the experiment helps Benjamin verify that the results are consistent and reliable, which is crucial for drawing valid conclusions about the effectiveness of the new plant fertilizer.

Front

What is Gabriella doing by recording flight times for each wing shape three times and finding the average?

Back

She is performing repeated trials of the experiment to increase the reliability of the results.

Answer explanation

Gabriella is performing repeated trials to ensure her results are reliable. By averaging the flight times from multiple trials, she minimizes the impact of random errors and increases the accuracy of her findings.

Front

Which of these experimental procedures is most likely to produce reliable data?

Back

A fertilizer is tested for its ability to increase the height of tomato plants. Plant height of several treatment groups are averaged over three trials. The experiment is sent to two other labs for replication.

Answer explanation

The fertilizer experiment is most reliable as it averages multiple trials and includes replication by other labs, enhancing data validity. Other options lack sufficient trials or replication, making them less reliable.

Front

Which conclusion is best supported by the results of a field test comparing GizmoBar and Whizobops Bar preferences among different age groups?

Back

GizmoBars were preferred by those between 10 and 35 years old.

Answer explanation

The results indicate that individuals aged 10 to 35 preferred GizmoBars over Whizobops Bars, supporting the conclusion that GizmoBars were favored by this age group.

Front

What should Samuel do if his experiment data does not support his hypothesis?

Back

Report his observations and conclusions honestly, clearly stating that the data do not support the hypothesis.

Answer explanation

Samuel should report his observations and conclusions honestly, stating that the data do not support his hypothesis. This is essential for scientific integrity and contributes to the body of knowledge.

Front

Why was it important that identical twins be involved in the 2017 NASA experiment involving Scott Kelley and Mark Kelley?

Back

Identical twins both have similar physical characteristics for scientists to test.

Answer explanation

Identical twins share similar physical characteristics, which allows scientists to control for genetic variables in the experiment. This makes it easier to isolate the effects of the environment and space travel on their bodies.