Step 2 Life Science Notes: Hypotheses, Experiment Planning, and Graphs
Guidelines for Formulating a Scientifically Sound Hypothesis
In the second step of life science methodology, the researcher must focus on the precise formulation of a hypothesis. This hypothesis serves as a foundational prediction that must be constructed as a written statement. Crucially, the hypothesis is required to be exactly one sentence in length. It must explicitly identify and include both the independent variable and the dependent variable to define the relationship being investigated. When writing the hypothesis, the researcher must use language that is clear, specific, and concise. It is mandatory that the statement does not include any explanations or reasons for the predicted outcome. Furthermore, the hypothesis must remain objective, ensuring there are no personal opinions or biases included in the text.
Detailed Procedures for Planning an Experiment and Defining an Aim
When transitioning to the step of planning an experiment, establishing a clear aim is essential. The aim is used to determine exactly what the researcher wants to achieve with the experiment. In drafting the aim, specific language must be employed, and both the independent variable and the dependent variable must be mentioned. The aim should provide a clear statement of the purpose of the experiment and should traditionally begin with the phrase "To determine…". It is vital to avoid making predictions within the aim itself; the aim is intended to define the objective rather than the expected result.
Standardized Conventions for the Construction of Time Graphs
The construction of time graphs in life sciences follows specific axial and labeling conventions to ensure accurate data representation. The horizontal axis of the graph is designated as the -axis, and it is upon this axis that the independent variable must be plotted. The vertical axis is designated as the -axis, which is reserved for the dependent variable. For the graph to be valid, each axis must be clearly labelled. Additionally, these labels must include the specific units of measurement, which should be enclosed in brackets. An example of this required labeling format provided in the transcript is .