Ratio - GCSE Biology Definition

In GCSE Biology, a ratio is a way to compare two or more quantities, showing how much of one thing there is compared to another. For example, if we are looking at the ratio of students who have blue eyes to those who have brown eyes in a class and there are 4 students with blue eyes and 8 with brown, the ratio is 4:8, which can be simplified to 1:2. This means for every one student with blue eyes, there are two with brown eyes. Ratios help us understand relationships and make comparisons in biology, such as comparing populations of different species or amounts of substances in experiments.