ATPL: The sleep cycles repeat during the course of a night's sleep.1. Each succeeding cycle contains a greater amount of REM-sleep.2. Frequent interruption of the REM-sleep may be harmful.
Question 226, Human Performance and Limitations - ATPL - Airline Transport Pilot license
Explanation: The sleep cycles repeat during the course of a night's sleep.1. Each succeeding cycle contains a greater amount of REM-sleep.2. Frequent interruption of the REM-sleep may be harmful.