A Level Biology Practice Exam

How is accuracy defined in scientific measurements?

1. The consistency of repeated measurements

2. The proximity of a measured value to the true value

3. The range of values obtained from an experiment

4. The resolution of the measuring instrument used

The correct answer is: The proximity of a measured value to the true value

Accuracy in scientific measurements refers specifically to how close a measured value is to the true or accepted value. It is a critical concept in experimental biology and other scientific disciplines, as it indicates the reliability of the results obtained from measurements. When a measurement is accurate, it means that the value obtained reflects the actual value of the quantity being measured, allowing researchers to make valid conclusions based on their experiments. This is essential in ensuring that the findings of an experiment can be trusted and applied in real-world scenarios. While consistency of repeated measurements relates to precision and signifies how reproducible results are, it does not address how close those measurements are to the true value. Similarly, the range of values obtained indicates variability in data but is not a measure of accuracy. Lastly, resolution pertains to the smallest increment that an instrument can measure, which affects the granularity of the measurement but not necessarily its accuracy. Therefore, being close to the true value is clearly the defining characteristic of accuracy in scientific measurements.