When a person dies, how long are each individual cells in their body alive for? How do they know to die too?
In: Biology
Without oxygen the cells is not able to generate ATP which is used in almost all of the biological reactions. So the cell quickly becames chemically inactive. It does not die as such but it will usually become damaged from things very quickly. There are always some damaging chemical reactions happening as wll as infections from bacteria and other things. And whithout the ability to defend itself, repair damage and replace cells the body quickly becomes inrepairable. This can take anything from a couple of minutes to a few hours. This is why chest compressions are so important as it will make sure that the blood still flows throughout the body delivering oxygen to the cells and removing toxins from them so they can at least protect themselves from damage. This means that if we are able to fix whatever caused the heart to stop in the first place the body may be able to recover.
Depending on body temperature; if the cells don’t get a supply of oxygen – you are looking at minutes.
People who drown in freezing water for 15 or 20 min (sometimes longer) will usually survive.
We should think about what it means to ‘die’ first. Generally when we say someone has died, we mean that brain activity has dropped to nothing and their heart has stopped beating. However, many of the cells in their body will still be alive. Without the heart and lungs, oxygen will not be moved around the body, and all cells need oxygen to survive, so the cells will start to die. How long this takes depends on several factors such as how cold the body is, but generally the longest would be somewhere around an hour or so, unless steps are taken to keep the cells alive like you would do if you wanted to preserve tissue for an organ transplant (in which case the cells can be kept alive for longer).
Once your heart stops pumping blood nd thus oxygen and nutrients around your body cells are inevitably going to die from lack of those things. How long varies for each cell type. Brain cells die in minutes where as skin cells could conceivably last for many hours.
No oxygen – > no ATP – > shrinking cross-membrane potential until eventually no signals are transmitted anymore.
Furthermore enzymes digest the membranes until the cells collabse. How long this takes depends on the cell type, for neurons its starting approximately 3 min after the heart stops beating, for skin cells 2 days
Latest Answers