Learning objective

Biological rhythms are natural cycles of bodily functions governed by an internal clock, specifically including: • circadian rhythms, which are the sleep-wake cycle repeating every 24 hours • ultradian rhythms, which are cycles occurring multiple times within a 24-hour period.

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Exam focus

Read the explanation.
Check key terms.
Practise with linked questions.

Cambridge IGCSE PsychologySleep and dreams

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Quick explanation

Biological rhythms are natural cycles of bodily functions governed by an internal clock, specifically including: • circadian rhythms, which are the sleep-wake cycle repeating every 24 hours • ultradian rhythms, which are cycles occurring multiple times within a 24-hour period

This point belongs to Biological rhythms, natural cycles of bodily processes regulated by a person’s internal ‘clock’,, especially Biological rhythms, natural cycles of bodily processes regulated by a person’s internal ‘clock’, outcomes.
You need to be able to biological rhythms are natural cycles of bodily functions governed by an internal clock, specifically including: • circadian rhythms, which are the sleep-wake cycle repeating every 24 hours • ultradian rhythms, which are cycles occurring multiple times within a 24-hour period.
The key ideas to know are Define, Describe, and Explain.
Use the linked flashcards and practice questions to check recall, then practise applying the idea in an exam-style answer.

Key concepts

DefineDescribeExplain

Why it matters

This objective helps connect Biological rhythms, natural cycles of bodily processes regulated by a person’s internal ‘clock’, outcomes to exam-style questions, flashcards, and revision notes for Biological rhythms, natural cycles of bodily processes regulated by a person’s internal ‘clock’,.

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