The science behind death

No.13515435 ViewReplyOriginalReport
Are there any researches on the process of dying? I always wondered how much of it has to do with stuff such as willpower and at which point it just runs down to basic biology/chemistry
How come a guy getting cut into two can survive for 45 minutes until emergency arrives and another one gets hit by a gun in the stomach and bleeds out on the spot within 10 minutes?