In a sleep laboratory, Leila's sleep is recorded through the night. During some periods her eyes dart about under her eyelids while the muscles of her body stay limp. Each of these periods ends one sleep cycle, and they come back several times during the night.
Identify the stage of sleep Leila is in during these periods.
State approximately how long one full sleep cycle lasts.
53 exam-style questions on OCR GCSE Psychology 6.1 Key Concepts, covering 6.1.1 Functions, features and benefits of sleep, 6.1.2 Causes of sleep disorders, and 6.1.3 Endogenous pacemakers and exogenous zeitgebers. Each one has a worked solution and a mark scheme showing where the marks go.