Because those are traces of life meaning that there was life living there once, that life wouldn't have been able to survive there with how Antarctica is now.
The two reactants are carbon dioxide and water.
The two products are oxygen and glucose.
Hope this helps!
Answer:
Without infection or decay on your food you are decreasing the risk of getting viruses like salmonella,food poisoning,Norovirus, etc. It could also help the less fortunate or homeless they would not have to worry about replacing their food due to decay or infection