Question

ens to the carbon-14 in a living organism when it dies?
is be used to establish how long ago the organism died?
ords in the left column to the appropriate blanks in the sentences on the right. make certain each sentence is complete before submi

decay
accumulate(s)
how long it took
initial quantity of
increase
half-life
period of growth
faster uptakes
further
no longer uptakes
remains

1. when an organism dies, it

carbon-14; therefore, the amount of carbon-14 starts to
at a rate equal to the
of carbon-14.

1. by measuring how much carbon-14

in an organism, you can use the
to
determine
the carbon-14 to
to the current level.

Explanation:

1. For the first sentence: When an organism dies, it no longer uptakes carbon - 14 (since living organisms take in carbon - 14, and death stops this process), so the amount of carbon - 14 starts to decay (carbon - 14 is a radioactive isotope that decays over time) at a rate equal to the half - life (half - life is the time it takes for half of a radioactive substance to decay, and the decay rate is related to the half - life) of carbon - 14.
2. For the second sentence: By measuring how much carbon - 14 remains (the amount left after decay) in an organism, you can use the half - life (to calculate the time elapsed) to determine how long it took (the time since death) the carbon - 14 to decay (from the initial amount) to the current level.

So the filled - in sentences are:

1. When an organism dies, it no longer uptakes carbon - 14; therefore, the amount of carbon - 14 starts to decay at a rate equal to the half - life of carbon - 14.
2. By measuring how much carbon - 14 remains in an organism, you can use the half - life to determine how long it took the carbon - 14 to decay to the current level.

Answer:

1. no longer uptakes; decay; half - life
2. remains; half - life; how long it took; decay