Physical effects of sleep deprivation

What are the physical effects of sleep deprivation?  Unfortunately, there are many effects of suffering through sleepless nights.  Some are just annoying, but others can be dangerous to your health.  Others could effect your employment.  No boss wants an employee who can’t think straight because they are tired, but that is exactly what happens when you are sleep deprived.   You are also irritable when sleepy.  After a few days of sleep deprivation, you can really start to feel the negative effects.  Some people even start to hallucinate.  And after weeks of sleep deprivation, test show some rats even died.