Scientific Method and Metric System Review

Flashcards covering key concepts from the lecture notes on the Scientific Method, Hypothesis, Variables, Experiments, Metric System, and Understanding Numerical Data (Statistics).

What is science?

Science is the knowledge of a particular subject.

What is the scientific method?

The scientific method is a procedure for testing ideas involving a series of interrelated steps.

List the steps of the scientific method.

Make observations, Ask questions, Develop a hypothesis, Make predictions, Test predictions by experimentation, Analyze and interpret results, Draw conclusions (reject or accept hypothesis).

What is a hypothesis?

An educated guess that explains a phenomenon or answers a scientific question, which should be testable and include a prediction.

What is a null hypothesis (Ho)?

A statement that there is no significant difference or effect between variables; it states no difference.

What is an independent variable?

The variable that is manipulated in an experiment and does not change with other variables. For example, fertilizer input.

What is a dependent variable?

The variable that is observed in a study and changes with a change in other variables. For example, quantity of algae.

What is an experimental group?

The group(s) in an experiment exposed to the independent variable, which then produces the dependent variable.

What is a control group?

The group in an experiment that is not exposed to the independent variable and serves as a standard for comparison.

What is the purpose of experiments in the scientific method?

Experiments provide data to determine if a hypothesis should be accepted or rejected.

What is the difference between a scientific question and a hypothesis?

A scientific question poses an inquiry about a phenomenon, whereas a hypothesis is a testable, educated guess that offers a potential explanation or answer to that question, often including a prediction for an experiment.

Why is repetition important in an experiment?

Repetition ensures reliability and helps confirm that observed effects are not due to other confounding factors. Experiments must be repeatable by other scientists with similar results.

What is the basic unit of length in the metric system?

Meter (m).

How are units of area expressed in the metric system?

As squared units of length (e.g., m²).

What is volume?

The space occupied by an object.

What is the basic metric unit of volume?

Liter (L).

List some devices used to measure volume.

Beaker, Erlenmeyer flask, Graduated cylinders, Pipets.

How should one read the volume of a liquid in a graduated cylinder?

Read the volume at eye level at the lowest/middle point of the meniscus (the curve of the liquid surface).

What is the basic unit of mass in the metric system?

Gram (g).

What device is commonly used to measure mass in a lab?

A triple-beam balance.

What unit do biologists typically use to measure temperature?

Degrees Celsius (°C).

What are statistics in the context of numerical data?

A way to organize, summarize, and describe data.

Define Mean (in statistics).

The average of a set of measurements, calculated by summing all measurements and dividing by the total number of measurements.

Define Median (in statistics).

The middle measurement in an ordered set of data.

Define Range (in statistics).

The difference between the highest and lowest measurements in a set of data.

Define Standard Deviation (SD).

The positive square root of the variance, used to measure the amount of variation or dispersion of a set of data values.