NJL52 said:
As far as I know:
The only state that 100% stops movement and chemical changes is absolute zero. And liquid nitrogen doesn't reach that so I imagine the neurons etc will die if frozen in nitrogen.
i believe it has something to do with the cell membrane bursting.
ice expands this creates a problem. it is still interesting though.
" Although some animals are able to lower their body temperatures during hibernation, most animals, like people, cannot tolerate freezing temperatures within their body tissues. Normally, when an organism is exposed to below-freezing temperatures, ice forms in smaller blood vessels and either bursts the blood vessels or stretches them beyond the point where they can function normally. In addition, ice in the blood vessels "captures" the water content, making it impossible for the blood cells to survive. Other types of cells are also damaged during freezing. Frostbite is a common malady caused by cold temperatures; frozen skin and blood cells are damaged from the dehydration due to freezing.
Scientists have discovered, however, that some varieties of frogs and turtles can actually survive being frozen. When these animals sense ice on the outsides of their bodies, their livers produce extra glucose (blood sugar), which floods into their cells to protect the cell from freezing and from damage. This also holds the cell's shape so it doesn't collapse upon itself. Nucleating proteins "guide" water out of the cells, allowing the water to go in between the cells and the organs. This allows the water to freeze, but in small pieces, without "spears" that could puncture the cell membrane. "
http://www.mansfieldct.org/schools/mms/staff/hand/heatcryo.htm