'Out of phase' describes when two or more repeating events, such as waves or biological cycles, do not occur at the same time — their peaks and troughs happen at different points. In GCSE Biology, this term is relevant when studying biological rhythms, like sleep cycles or hormone release patterns. When processes are out of phase, they are not synchronised, which can affect how well body systems work together. Understanding whether biological cycles are in or out of phase helps explain how living organisms maintain coordination and balance.
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