The scientific method
Science is not simply a collection of facts. A typical investigation starts with an observation or question, followed by a possible explanation that can be tested. Evidence is gathered through observations, measurements or experiments, and the results are used to refine the explanation. Repeating tests and allowing other people to examine the evidence are important parts of reliable science.
Physics, chemistry and biology
Physics studies matter, energy, forces and the rules that describe how physical systems behave. Chemistry focuses on substances, their properties and the reactions that transform them. Biology studies living organisms, from individual cells to whole ecosystems. These areas overlap constantly: for example, biology depends on chemistry, while medical imaging draws on physics.
Science in everyday life
Scientific ideas are not limited to laboratories. Cooking involves chemical reactions, weather forecasts use observations and physical models, medicines are developed through biological and chemical research, and modern communications depend on physics and engineering. Understanding the basic principles can make ordinary experiences easier to explain and investigate.
How to use a quiz as a learning tool
A quiz is most useful when a wrong answer becomes an opportunity to learn. Try answering before looking anything up, then read the explanation carefully. If a question introduces an unfamiliar idea, use it as a starting point for further reading rather than treating the score as the end of the exercise.
Evidence, correlation and causation
Two things happening together does not automatically mean that one caused the other. For example, an increase in ice-cream sales and an increase in swimming accidents might occur during hot weather; that does not mean ice cream causes accidents. Temperature can influence both. To assess a scientific claim, look for a plausible mechanism, consider other explanations and check whether the evidence comes from a fair test or a well-designed study. A single example or coincidence is rarely enough to establish cause and effect.
A practical example: testing a claim
Imagine someone claims that a plant grows faster when it hears music. A fair test would use similar plants, the same soil, water, light and temperature, changing only the sound condition. Measure growth over the same period, repeat the test with several plants and record the results before deciding whether the evidence supports the claim. This illustrates why controlled comparisons and repeatable evidence matter more than a single observation.
Further reading
These links provide further reading from established organisations, including subject explanations, source material and reference databases. They are not citations for every sentence in this guide.