What is the function of the start codon of an mrna sequence?

a. the start codon acts as a checkpoint in the eukaryotic cell cycle.
b. the start codon protects the mrna from being degraded.
c. the start codon signals for the ribosome to begin assembling amino acids at that point in the mrna sequence.
d. the start codon signals for the ribosome to release the mrna sequence.

Option no. C is the correct answer.

The start codon signals for the ribosome to begin assembling amino acids at that point in the mRNA sequence.

relative dating involves things like higher layers are most recent than rocks lower in the sequence. this can be extended to the known sequence of fossils. rocks containing rabbit fossils are later than those containing dinosaur fossils.  

absolute dating methods mainly use radioactive elements that have known rates of decay and produce recognizable products. for example potassium 40 decays to produce argon. once a rock has solidified the argon is trapped. by measuring the argon and potassium0 you can get an accurate number for the age.  

some other methods are good for archaeological ages. dendrochronology involves recognizing the sequence of tree rings. the orientation of magnetized particles in baked clay can be used to date a fire.

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