A theatre technician has been working indoors. The table shows the light reaching their eyes during one evening and the next morning.
| Time | Light reaching the technician's eyes |
|---|---|
| 20:00 | Bright indoor lighting |
| 22:00 | Dim lighting |
| 23:30 | A bright work light |
| 07:00 | Bright daylight |
Which statement correctly predicts the pattern of melatonin secretion by the pineal gland?
Secretion stays low at 20:00, begins to rise in the dim light at 22:00, is slowed by the bright light at 23:30 and is switched off by daylight at 07:00.
Secretion rises at 20:00, falls in the dim light at 22:00, rises again under the bright light at 23:30 and stays high in daylight at 07:00.
Secretion stays low in the dim light at 22:00, rises under the bright light at 23:30 and increases further when daylight reaches the eyes at 07:00.
Secretion is controlled by clock time alone, so it rises after 22:00 and is unchanged by the bright light at 23:30 or daylight at 07:00.
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.