Answer:
Sleep deprivation in general, is a very serious situation because it will affect the entire human system, and it can lead to severe health conditions, and even death.
In performing activities that require high levels of focus and coordination, like driving, a person requires all of his senses to be on keen alert, and all his reflexes and movements must be under control and coordinated.
However, sleep deprivation is considered today as serious as consuming alcohol when driving, because this situation deprives the brain, and the body at large, from that much needed coordination and control that it would have if it were rested. As such, when a person is sleep deprived, depending on the severity of the deprivation, they can loose coordination, loose control of their reflexes, lose focus, have memory and judgement impairment and even go so far as to suffer from narcolepsy, a condition in which the person literally loses all control of his body due to sleep deprivation. Basically, they fall asleep in the car. This can cause accidents that lead to death.
