Age dating equation
Gneiss Samples from outcrops in the Karelian area of eastern Finland are believed to represent the oldest rocks in the Baltic region.
These rocks intrude even older rocks that have not been dated.
So if we put the last two equations together, we get this Which is entirely in terms of things we can measure in the lab.
The half-life of an isotope is a more intuitive measure, the half-life is a unit of time over which half of the radioactive atoms in a given population will decay.
You can easily see the relationship between the decay constant (λ) and half-life (t, half of the parents have decayed and turned into daughters, so N=D, and D/N = 1.
Carbon is a key element in biologically important molecules.
During the lifetime of an organism, carbon is brought into the cell from the environment in the form of either carbon dioxide or carbon-based food molecules such as glucose; then used to build biologically important molecules such as sugars, proteins, fats, and nucleic acids.