The Ratio of Carbon-14 (¹⁴C) to Its Stable Isotope, Carbon-12

question 207

Multiple Choice

The ratio of carbon-14 (¹⁴C) to its stable isotope, carbon-12 (¹²C) , is relatively constant in living organisms and their environment; however, this changes once an organism dies.In a fossil approximately 40,000 years old,

• A) the ratio of ¹⁴C to ¹²C would be higher because the ¹²C is not replenished after death.
• B) the ratio of ¹⁴C to ¹²C would be lower because the ¹⁴C is not replenished after death.
• C) the ratio of ¹⁴C to ¹²C would not change because the ¹⁴C is replenished after death.
• D) the ratio of ¹⁴C to ¹²C would be equal (1:1).
• E) the ¹⁴C would be completely gone; all remaining carbon by this time would be ¹²C.

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Definitions:

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A randomized clinical trial is a scientific study where participants are randomly assigned to different groups to compare the effects of various treatments or interventions.

Biomedical Therapy

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A group of psychotherapeutic approaches aimed at addressing dysfunctional emotions, behaviors, and thoughts through systematic, goal-oriented procedures.

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