When this is over, the cycle starts over; the original star dies and becomes a white dwarf. White Dwarf The core of a white dwarf star surrounds itself with layers of hydrogen, which still burn, continuing to fuse.
REM sleep is important because it is the restorative part of our sleep cycle. Typically, you begin the sleep cycle with a period of non-REM sleep followed by a very short period of REM sleep. The period of non-REM sleep is made up of stages 1 to 4. Each stage can last from 5 to 15 minutes.
Stage 5 - REM Sleep: REM sleep usually occurs in cycles during the last 5-6 hours of an 8-hour nightâs sleep. So how much sleep we get in this stage will depend on how much sleep we get for the night. During REM sleep, eye movements increase, heart rate increases, and the normal body processes also increase.