Molecules In All Organisms Are Composed In Part Of Radioactive Carbon-14. Which Statement Best Explains The Presence Of Carbon-14 In Organisms?. It is formed in the atmosphere when cosmic. The radioactive isotope reacts in the.

This is a continuous process, so more 14 c is always being created. It is formed in the atmosphere when cosmic. ^ {14}c) is a radioactive isotope of carbon that is present in all living organisms.