Physiology General 7e02d85b Without external cue, the sleep-wake cycle in humans A Unchanged B Continues with cycle length of > 24 hours C Continues with cycle length of < 24 hours D Continue with cycle length of > 12 hours High-Yield Explanation Normal sleep-wake cycle in humans- 24 hrs When external cues (Light and darkness) removed, sleep-wake cycle- Slightly increased (>24hrs)