Scientific Experiments and Data Analysis

A scientist is studying the effect of fertilizer concentration on plant growth. They prepare four groups of plants, each receiving a different concentration of fertilizer, and measure their heights after two weeks. Which type of graph is most appropriate for presenting this data?

A research team is investigating the step-by-step process of cellular respiration. Which type of chart would be most effective in illustrating this process?

In an experiment, researchers found a strong positive correlation between the amount of rainfall and the yield of corn crops. One variable directly impacts the other. In plotting these variables on a line graph, which variable should be placed on the x-axis?

A researcher is analyzing the distribution of blood types in a population. Which type of chart would be most effective for visualizing the percentage of people with each blood type (A, B, AB, O)?

A scientist is conducting an experiment to test a hypothesis. After collecting and evaluating the data, the results contradict the initial hypothesis. What is the next appropriate step in the scientific method?

Scientific Experiment Steps

Scientific experiments involve six key steps.
These steps are: observation, hypothesis formation, experiment design and execution, data collection and evaluation, hypothesis acceptance or rejection, and, if necessary, the creation of a new hypothesis.
Data from experiments can be shown in various formats to help researchers analyze data and spot trends.

Graph and Chart Types

Line graphs are useful for comparing minor changes in a trend over a period.
They are also useful when comparing numerical data.
Bar charts are suited to comparing larger changes or differences in data across different groups.
They are also suited to comparisons of numerical and categorical data.
Pie charts are used to compare percentages.
They are also used to compare numerical and categorical data.
Flow charts show the relationship between concepts or steps in a process.
They are also used to compare non-numerical data.

Data Analysis

Each method of data display requires its own analysis technique.
Line graphs demonstrate relationships between dependent and independent variables.
They achieve this by plotting coordinate pairs along the x and y-axes.
The x-axis is horizontal.
The x-axis plots the independent variable, or the cause.
The independent variable is not affected by other variables.
The y-axis is vertical.
The y-axis plots the dependent variable.
The dependent variable is affected by the independent variable.