Sleep has two phases: non-rapid eye movement (NREM) and rapid eye movement (REM). It also has four stages that repeat in 4 to 6 cycles nightly. Each stage affects your body differently, from light ...

Figure 2: Complete loss of Rom-1 results in apoptotic rod photoreceptor death. Figure 3: The loss of Rom-1 leads to the development of short ROSs, which exhibit a biphasic pattern of disorganization.