Scientific Research: Steps and Concepts

Scientific Research Overview

  • Scientific research is conducted to create new knowledge in science.
    • E.g., discovering a new species or determining the function of a hormone.

Steps in Scientific Research

  1. Ask Question

    • Identify a problem that can be tested.
    • Example: Does salt water have a higher boiling point than pure water?

  2. Determine Hypothesis

    • A hypothesis is a statement based on expectations.
    • It is an explanation of an observation that can be accepted or rejected.
    • Example: The more salt you put into water, the higher the boiling point.

  3. Design Experiment

    • Follow a step-by-step method similar to a recipe to collect data.
    • Example: Gather solutions with different salt concentrations, heat them, and record their boiling points.

  4. Collect Data

    • Perform the experiment and record the data.
    • Use three types of variables to record the information.

  5. Analyze Data

    • Draw a graph to determine the relationship between variables and observe patterns.
    • Independent variables are plotted on the x-axis, while dependent variables are plotted on the y-axis.

  6. Make Conclusion

    • Decide whether to accept or reject the hypothesis and provide reasons for the decision.

Variables in Experiments

  • Independent Variables:
    • Pre-determined variables that are manipulated (e.g., amount of salt).
  • Dependent Variables:
    • Measured variables affected by the independent variable (e.g., boiling point).
  • Constant Variables:
    • Variables that remain unchanged throughout the experiment (e.g., volume of the solutions).
Example of Variables
  • Independent: Amount of salt
  • Dependent: Boiling point
  • Constant: Volume of solutions, etc.

Control Group

  • It is compared with results to determine changes (e.g., pure water).
  • Helps ascertain whether changes in the dependent variable are due to the manipulation of the independent variable.
Example of Control Group
  • Independent Variable: Amount of water
  • Dependent Variable: Fraction of seeds that sprout.
    • Experimental Group: + Water
    • Control Group: - Water
    • Results: 9/10 seeds sprout vs. 0/10 seeds sprout.

Reliability in Research

  • To make results more meaningful:
    • Repeat the investigation.
    • Increase the sample size.

Validity in Research

  • Ensure certain variables are constant to maintain the validity of the results.
    • This applies aside from independent and dependent variables.

Analyzing Data

  • Construct graphs to illustrate the relationship between variables and to identify patterns.

Conclusion of Experiment

  • Accept or reject your hypothesis based on the analyzed data, providing justification for your decision.